feat(P3): IHF Phase 3 complete — Governance and Decision Linkage

Implements the full governance layer:
- Schema: requirements, decision_records, policy_references,
  implementation_change_references; requirement_candidates gets
  requirement_id back-reference
- RequirementsController (index/show; promotion-only create)
- DecisionRecordsController (CRUD + policy/impl ref management)
- GovernanceDashboardAction on HubsController (AutoRefresh)
- PromoteToRequirementAction + LinkToDecisionAction on candidates
- Outcome immutability enforced at controller level (fill excludes outcome)
- Full six-outcome vocabulary with Tailwind color roles
- Integration tests for all Phase 3 paths
- FrontController: registers Phase 2 missing controllers + all Phase 3
- SCOPE.md + docs/phase3-summary.md updated

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Web/View/DecisionRecords/Edit.hs

@@ -0,0 +1,34 @@
+module Web.View.DecisionRecords.Edit where
+
+import Web.Types
+import Generated.Types
+import IHP.Prelude
+import IHP.ViewPrelude
+import Web.View.DecisionRecords.New (renderForm)
+
+data EditView = EditView
+    { record       :: !DecisionRecord
+    , requirements :: ![Requirement]
+    , candidates   :: ![RequirementCandidate]
+    , users        :: ![User]
+    }
+
+instance View EditView where
+    html EditView { .. } = [hsx|
+        <div class="mb-6 flex items-center gap-2 text-sm text-gray-500">
+            <a href={DecisionRecordsAction} class="hover:text-gray-700">Decisions</a>
+            <span>/</span>
+            <a href={ShowDecisionRecordAction { decisionRecordId = record.id }}
+               class="hover:text-gray-700">{record.title}</a>
+            <span>/</span>
+            <span>Edit</span>
+        </div>
+
+        <div class="max-w-2xl">
+            <h1 class="text-2xl font-semibold mb-2">Edit Decision Record</h1>
+            <p class="text-sm text-amber-600 mb-6">
+                Note: outcome is immutable and cannot be changed here.
+            </p>
+            {renderForm record requirements candidates users (UpdateDecisionRecordAction { decisionRecordId = record.id })}
+        </div>
+    |]

Web/View/DecisionRecords/Index.hs

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+module Web.View.DecisionRecords.Index where
+
+import Web.Types
+import Generated.Types
+import IHP.Prelude
+import IHP.ViewPrelude
+
+data IndexView = IndexView
+    { records        :: ![DecisionRecord]
+    , requirements   :: ![Requirement]
+    , users          :: ![User]
+    , mOutcomeFilter :: !(Maybe Text)
+    }
+
+allOutcomes :: [Text]
+allOutcomes = ["accepted", "rejected", "deferred", "split", "merged", "reframed"]
+
+instance View IndexView where
+    html IndexView { .. } = [hsx|
+        <div class="flex items-center justify-between mb-6">
+            <h1 class="text-2xl font-semibold">Decision Records</h1>
+            <a href={NewDecisionRecordAction}
+               class="bg-indigo-600 text-white text-sm px-4 py-2 rounded hover:bg-indigo-700">
+                New Decision
+            </a>
+        </div>
+
+        <!-- Outcome filter tabs -->
+        <div class="flex gap-2 mb-5 text-sm flex-wrap">
+            <a href={DecisionRecordsAction}
+               class={filterTabClass Nothing mOutcomeFilter}>All</a>
+            {forEach allOutcomes (\o -> [hsx|
+                <a href={decisionFilterUrl o}
+                   class={filterTabClass (Just o) mOutcomeFilter}>{o}</a>
+            |])}
+        </div>
+
+        {if null records
+            then [hsx|<p class="text-sm text-gray-400">No decision records found.</p>|]
+            else renderTable records requirements users}
+    |]
+
+decisionFilterUrl :: Text -> Text
+decisionFilterUrl o = "/DecisionRecords?outcome=" <> o
+
+renderTable :: [DecisionRecord] -> [Requirement] -> [User] -> Html
+renderTable records reqs users = [hsx|
+    <div class="bg-white rounded-lg border border-gray-200 overflow-hidden">
+        <table class="w-full text-sm">
+            <thead class="bg-gray-50 border-b border-gray-200">
+                <tr>
+                    <th class="text-left px-4 py-3 font-medium text-gray-600">Title</th>
+                    <th class="text-left px-4 py-3 font-medium text-gray-600">Outcome</th>
+                    <th class="text-left px-4 py-3 font-medium text-gray-600">Requirement</th>
+                    <th class="text-left px-4 py-3 font-medium text-gray-600">Decided By</th>
+                    <th class="text-left px-4 py-3 font-medium text-gray-600">Decided At</th>
+                </tr>
+            </thead>
+            <tbody class="divide-y divide-gray-100">
+                {forEach records (renderRow reqs users)}
+            </tbody>
+        </table>
+    </div>
+|]
+
+renderRow :: [Requirement] -> [User] -> DecisionRecord -> Html
+renderRow reqs users dr = [hsx|
+    <tr class="hover:bg-gray-50">
+        <td class="px-4 py-3">
+            <a href={ShowDecisionRecordAction { decisionRecordId = dr.id }}
+               class="text-indigo-600 hover:text-indigo-800 font-medium">{dr.title}</a>
+        </td>
+        <td class="px-4 py-3">
+            <span class={outcomeClass dr.outcome <> " text-xs px-2 py-0.5 rounded font-medium"}>
+                {dr.outcome}
+            </span>
+        </td>
+        <td class="px-4 py-3 text-gray-600">
+            {linkedReqTitle reqs dr.requirementId}
+        </td>
+        <td class="px-4 py-3 text-gray-600">
+            {userName users dr.decidedBy}
+        </td>
+        <td class="px-4 py-3 text-gray-400 text-xs">{show dr.decidedAt}</td>
+    </tr>
+|]
+
+linkedReqTitle :: [Requirement] -> Maybe (Id Requirement) -> Text
+linkedReqTitle _    Nothing    = "—"
+linkedReqTitle reqs (Just rid) = maybe "(unknown)" (.title) (find (\r -> r.id == rid) reqs)
+
+userName :: [User] -> Maybe (Id User) -> Text
+userName _     Nothing    = "—"
+userName users (Just uid) = maybe "(unknown)" (.name) (find (\u -> u.id == uid) users)
+
+outcomeClass :: Text -> Text
+outcomeClass "accepted"  = "bg-green-100 text-green-800"
+outcomeClass "rejected"  = "bg-red-100 text-red-800"
+outcomeClass "deferred"  = "bg-gray-100 text-gray-600"
+outcomeClass "split"     = "bg-purple-100 text-purple-800"
+outcomeClass "merged"    = "bg-indigo-100 text-indigo-800"
+outcomeClass "reframed"  = "bg-orange-100 text-orange-800"
+outcomeClass _           = "bg-gray-100 text-gray-600"
+
+filterTabClass :: Maybe Text -> Maybe Text -> Text
+filterTabClass a b
+    | a == b    = "px-3 py-1.5 rounded bg-indigo-100 text-indigo-700 font-medium"
+    | otherwise = "px-3 py-1.5 rounded text-gray-600 hover:bg-gray-100"

Web/View/DecisionRecords/New.hs

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+module Web.View.DecisionRecords.New where
+
+import Web.Types
+import Generated.Types
+import IHP.Prelude
+import IHP.ViewPrelude
+
+data NewView = NewView
+    { record       :: !DecisionRecord
+    , requirements :: ![Requirement]
+    , candidates   :: ![RequirementCandidate]
+    , users        :: ![User]
+    }
+
+instance View NewView where
+    html NewView { .. } = [hsx|
+        <div class="mb-6 flex items-center gap-2 text-sm text-gray-500">
+            <a href={DecisionRecordsAction} class="hover:text-gray-700">Decisions</a>
+            <span>/</span>
+            <span>New</span>
+        </div>
+
+        <div class="max-w-2xl">
+            <h1 class="text-2xl font-semibold mb-6">New Decision Record</h1>
+            {renderForm record requirements candidates users CreateDecisionRecordAction}
+        </div>
+    |]
+
+renderForm :: DecisionRecord -> [Requirement] -> [RequirementCandidate] -> [User] -> action -> Html
+renderForm record requirements candidates users submitAction = [hsx|
+    <form method="POST" action={submitAction} class="bg-white rounded-lg border border-gray-200 px-6 py-5 space-y-4">
+        {hiddenField "authenticity_token"}
+
+        <div>
+            <label class="block text-sm font-medium text-gray-700 mb-1">Title</label>
+            <input type="text" name="title" value={record.title}
+                   class="w-full border border-gray-300 rounded px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-indigo-500"
+                   required />
+        </div>
+
+        <div>
+            <label class="block text-sm font-medium text-gray-700 mb-1">Outcome</label>
+            <select name="outcome"
+                    class="w-full border border-gray-300 rounded px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-indigo-500">
+                <option value="accepted">accepted</option>
+                <option value="rejected">rejected</option>
+                <option value="deferred">deferred</option>
+                <option value="split">split</option>
+                <option value="merged">merged</option>
+                <option value="reframed">reframed</option>
+            </select>
+            <p class="text-xs text-gray-400 mt-1">Outcome cannot be changed after creation.</p>
+        </div>
+
+        <div>
+            <label class="block text-sm font-medium text-gray-700 mb-1">Rationale</label>
+            <textarea name="rationale" rows="4"
+                      class="w-full border border-gray-300 rounded px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-indigo-500"
+                      required>{record.rationale}</textarea>
+        </div>
+
+        <div>
+            <label class="block text-sm font-medium text-gray-700 mb-1">Linked Requirement (optional)</label>
+            <select name="requirementId"
+                    class="w-full border border-gray-300 rounded px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-indigo-500">
+                <option value="">— None —</option>
+                {forEach requirements (\r -> [hsx|<option value={show r.id}>{r.title}</option>|])}
+            </select>
+        </div>
+
+        <div>
+            <label class="block text-sm font-medium text-gray-700 mb-1">Linked Candidate (optional)</label>
+            <select name="candidateId"
+                    class="w-full border border-gray-300 rounded px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-indigo-500">
+                <option value="">— None —</option>
+                {forEach candidates (\c -> [hsx|<option value={show c.id}>{c.title}</option>|])}
+            </select>
+        </div>
+
+        <div>
+            <label class="block text-sm font-medium text-gray-700 mb-1">Notes (optional)</label>
+            <textarea name="notes" rows="2"
+                      class="w-full border border-gray-300 rounded px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-indigo-500"
+                      placeholder="For split/merged: list related candidate IDs or context"
+                      >{maybe "" id record.notes}</textarea>
+        </div>
+
+        <div class="flex gap-3 pt-2">
+            <button type="submit"
+                    class="bg-indigo-600 text-white text-sm px-4 py-2 rounded hover:bg-indigo-700">
+                Create Decision
+            </button>
+            <a href={DecisionRecordsAction}
+               class="text-sm text-gray-500 px-4 py-2 rounded hover:bg-gray-100">Cancel</a>
+        </div>
+    </form>
+|]

Web/View/DecisionRecords/Show.hs

@@ -0,0 +1,206 @@
+module Web.View.DecisionRecords.Show where
+
+import Web.Types
+import Generated.Types
+import IHP.Prelude
+import IHP.ViewPrelude
+
+data ShowView = ShowView
+    { record       :: !DecisionRecord
+    , policyRefs   :: ![PolicyReference]
+    , implRefs     :: ![ImplementationChangeReference]
+    , mRequirement :: !(Maybe Requirement)
+    , mCandidate   :: !(Maybe RequirementCandidate)
+    , users        :: ![User]
+    }
+
+instance View ShowView where
+    html ShowView { .. } = [hsx|
+        <div class="mb-6 flex items-center gap-2 text-sm text-gray-500">
+            <a href={DecisionRecordsAction} class="hover:text-gray-700">Decisions</a>
+            <span>/</span>
+            <span>{record.title}</span>
+        </div>
+
+        <div class="max-w-3xl space-y-6">
+            <!-- Header card -->
+            <div class="bg-white rounded-lg border border-gray-200 px-6 py-5">
+                <div class="flex items-start justify-between mb-3">
+                    <h1 class="text-2xl font-semibold">{record.title}</h1>
+                    <div class="flex gap-2 ml-4">
+                        <span class={outcomeClass record.outcome <> " text-xs px-2 py-0.5 rounded font-medium"}>
+                            {record.outcome}
+                        </span>
+                        <a href={EditDecisionRecordAction { decisionRecordId = record.id }}
+                           class="text-sm border border-gray-300 px-3 py-1.5 rounded hover:bg-gray-50">
+                            Edit
+                        </a>
+                    </div>
+                </div>
+                <div class="text-xs text-gray-400 mb-3">
+                    Decided by: {userName users record.decidedBy} · {show record.decidedAt}
+                </div>
+                <div class="mb-3">
+                    <p class="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-1">Rationale</p>
+                    <p class="text-sm text-gray-700 leading-relaxed">{record.rationale}</p>
+                </div>
+                {maybe mempty renderNotes record.notes}
+            </div>
+
+            <!-- Linked requirement -->
+            <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
+                <h2 class="text-sm font-semibold text-gray-700 mb-2">Linked Requirement</h2>
+                {case mRequirement of
+                    Nothing  -> [hsx|<p class="text-sm text-gray-400">No requirement linked.</p>|]
+                    Just req -> [hsx|
+                        <a href={ShowRequirementAction { requirementId = req.id }}
+                           class="text-sm text-indigo-600 hover:text-indigo-800">{req.title}</a>
+                    |]}
+            </div>
+
+            <!-- Source candidate -->
+            {maybe mempty renderCandidateSection mCandidate}
+
+            <!-- Policy references -->
+            <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
+                <h2 class="text-sm font-semibold text-gray-700 mb-3">Policy References</h2>
+                {forEach policyRefs renderPolicyRef}
+                <form method="POST" action={AddPolicyReferenceAction { decisionRecordId = record.id }}
+                      class="mt-3 flex items-end gap-2">
+                    {hiddenField "authenticity_token"}
+                    <div>
+                        <label class="text-xs text-gray-500 block mb-1">Scope</label>
+                        <select name="policyScope"
+                                class="text-sm border border-gray-300 rounded px-2 py-1.5">
+                            <option value="internal">internal</option>
+                            <option value="external">external</option>
+                            <option value="regulatory">regulatory</option>
+                            <option value="contractual">contractual</option>
+                            <option value="architectural">architectural</option>
+                        </select>
+                    </div>
+                    <div class="flex-1">
+                        <label class="text-xs text-gray-500 block mb-1">Constraint note (optional)</label>
+                        <input type="text" name="constraintNote"
+                               class="w-full text-sm border border-gray-300 rounded px-2 py-1.5"
+                               placeholder="e.g. GDPR Art. 17 right-to-erasure" />
+                    </div>
+                    <button type="submit"
+                            class="text-sm bg-gray-100 border border-gray-300 px-3 py-1.5 rounded hover:bg-gray-200">
+                        Add
+                    </button>
+                </form>
+            </div>
+
+            <!-- Implementation references -->
+            <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
+                <h2 class="text-sm font-semibold text-gray-700 mb-3">Implementation References</h2>
+                {forEach implRefs renderImplRef}
+                <form method="POST" action={AddImplementationRefAction { decisionRecordId = record.id }}
+                      class="mt-3 flex items-end gap-2">
+                    {hiddenField "authenticity_token"}
+                    <div>
+                        <label class="text-xs text-gray-500 block mb-1">System</label>
+                        <select name="system"
+                                class="text-sm border border-gray-300 rounded px-2 py-1.5">
+                            <option value="github">github</option>
+                            <option value="linear">linear</option>
+                            <option value="jira">jira</option>
+                            <option value="other">other</option>
+                        </select>
+                    </div>
+                    <div class="flex-1">
+                        <label class="text-xs text-gray-500 block mb-1">Work item ref</label>
+                        <input type="text" name="workItemRef"
+                               class="w-full text-sm border border-gray-300 rounded px-2 py-1.5"
+                               placeholder="e.g. #1234, PROJ-456" />
+                    </div>
+                    <button type="submit"
+                            class="text-sm bg-gray-100 border border-gray-300 px-3 py-1.5 rounded hover:bg-gray-200">
+                        Add
+                    </button>
+                </form>
+            </div>
+        </div>
+    |]
+
+renderNotes :: Text -> Html
+renderNotes notes = [hsx|
+    <div class="mt-2">
+        <p class="text-xs font-semibold text-gray-500 uppercase tracking-wide mb-1">Notes</p>
+        <p class="text-sm text-gray-600 italic">{notes}</p>
+    </div>
+|]
+
+renderCandidateSection :: RequirementCandidate -> Html
+renderCandidateSection c = [hsx|
+    <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
+        <h2 class="text-sm font-semibold text-gray-700 mb-2">Source Candidate</h2>
+        <a href={ShowRequirementCandidateAction { requirementCandidateId = c.id }}
+           class="text-sm text-indigo-600 hover:text-indigo-800">{c.title}</a>
+    </div>
+|]
+
+renderPolicyRef :: PolicyReference -> Html
+renderPolicyRef ref = [hsx|
+    <div class="flex items-start justify-between py-2 border-b border-gray-100 last:border-0">
+        <div class="flex items-center gap-2 text-sm">
+            <span class={policyScopeClass ref.policyScope <> " text-xs px-2 py-0.5 rounded font-medium"}>
+                {ref.policyScope}
+            </span>
+            {maybe mempty (\n -> [hsx|<span class="text-gray-600">{n}</span>|]) ref.constraintNote}
+            <span class="text-xs text-gray-400">{show ref.createdAt}</span>
+        </div>
+        <form method="POST"
+              action={DeletePolicyReferenceAction { policyReferenceId = ref.id }}>
+            {hiddenField "authenticity_token"}
+            <button type="submit"
+                    class="text-xs text-red-500 hover:text-red-700 ml-2">Remove</button>
+        </form>
+    </div>
+|]
+
+renderImplRef :: ImplementationChangeReference -> Html
+renderImplRef ref = [hsx|
+    <div class="flex items-start justify-between py-2 border-b border-gray-100 last:border-0">
+        <div class="flex items-center gap-2 text-sm">
+            <span class={systemBadgeClass ref.system <> " text-xs px-2 py-0.5 rounded font-medium"}>
+                {ref.system}
+            </span>
+            <span class="font-mono text-gray-700">{ref.workItemRef}</span>
+            <span class="text-xs text-gray-400">{show ref.linkedAt}</span>
+        </div>
+        <form method="POST"
+              action={DeleteImplementationRefAction { implementationChangeReferenceId = ref.id }}>
+            {hiddenField "authenticity_token"}
+            <button type="submit"
+                    class="text-xs text-red-500 hover:text-red-700 ml-2">Remove</button>
+        </form>
+    </div>
+|]
+
+outcomeClass :: Text -> Text
+outcomeClass "accepted"  = "bg-green-100 text-green-800"
+outcomeClass "rejected"  = "bg-red-100 text-red-800"
+outcomeClass "deferred"  = "bg-gray-100 text-gray-600"
+outcomeClass "split"     = "bg-purple-100 text-purple-800"
+outcomeClass "merged"    = "bg-indigo-100 text-indigo-800"
+outcomeClass "reframed"  = "bg-orange-100 text-orange-800"
+outcomeClass _           = "bg-gray-100 text-gray-600"
+
+policyScopeClass :: Text -> Text
+policyScopeClass "regulatory"   = "bg-red-50 text-red-700 border border-red-200"
+policyScopeClass "contractual"  = "bg-orange-50 text-orange-700 border border-orange-200"
+policyScopeClass "external"     = "bg-yellow-50 text-yellow-700 border border-yellow-200"
+policyScopeClass "architectural"= "bg-blue-50 text-blue-700 border border-blue-200"
+policyScopeClass _              = "bg-gray-50 text-gray-600 border border-gray-200"
+
+systemBadgeClass :: Text -> Text
+systemBadgeClass "github" = "bg-gray-800 text-white"
+systemBadgeClass "linear" = "bg-violet-100 text-violet-800"
+systemBadgeClass "jira"   = "bg-blue-100 text-blue-800"
+systemBadgeClass _        = "bg-gray-100 text-gray-600"
+
+userName :: [User] -> Maybe (Id User) -> Text
+userName _     Nothing    = "—"
+userName users (Just uid) = maybe "(unknown)" (.name) (find (\u -> u.id == uid) users)

Web/View/Hubs/GovernanceDashboard.hs

@@ -0,0 +1,206 @@
+module Web.View.Hubs.GovernanceDashboard where
+
+import Web.Types
+import Generated.Types
+import IHP.Prelude
+import IHP.ViewPrelude
+
+data GovernanceDashboardView = GovernanceDashboardView
+    { hub              :: !Hub
+    , widgets          :: ![Widget]
+    , allCandidates    :: ![RequirementCandidate]
+    , allRequirements  :: ![Requirement]
+    , recentDecisions  :: ![DecisionRecord]
+    , allDecisions     :: ![DecisionRecord]
+    , allAnnotations   :: ![Annotation]
+    }
+
+instance View GovernanceDashboardView where
+    html GovernanceDashboardView { .. } = [hsx|
+        <div class="mb-6 flex items-center justify-between">
+            <div>
+                <div class="flex items-center gap-2 text-sm text-gray-500 mb-1">
+                    <a href={HubsAction} class="hover:text-gray-700">Hubs</a>
+                    <span>/</span>
+                    <a href={ShowHubAction { hubId = hub.id }} class="hover:text-gray-700">{hub.name}</a>
+                    <span>/</span>
+                    <span>Governance</span>
+                </div>
+                <h1 class="text-2xl font-semibold">Governance Dashboard — {hub.name}</h1>
+            </div>
+            <div class="flex gap-2">
+                <a href={TriageDashboardAction { hubId = hub.id }}
+                   class="text-sm border border-gray-300 px-3 py-1.5 rounded hover:bg-gray-50">
+                    Triage Dashboard
+                </a>
+                <a href={ShowHubAction { hubId = hub.id }}
+                   class="text-sm border border-gray-300 px-3 py-1.5 rounded hover:bg-gray-50">
+                    Hub Overview
+                </a>
+            </div>
+        </div>
+
+        <!-- KPI row: decision outcomes -->
+        <div class="grid grid-cols-3 gap-4 mb-6 sm:grid-cols-6">
+            {forEach outcomeList (\o -> renderKpiCard o (countOutcome allDecisions o))}
+        </div>
+
+        <!-- Open requirements awaiting decision -->
+        <div class="bg-white rounded-lg border border-gray-200 px-6 py-5 mb-6">
+            <h2 class="text-sm font-semibold text-gray-700 mb-3">
+                Open Requirements Awaiting Decision
+                <span class="ml-2 text-xs font-normal text-gray-400">
+                    ({show (length awaitingDecision)} pending)
+                </span>
+            </h2>
+            {if null awaitingDecision
+                then [hsx|<p class="text-sm text-gray-400">All requirements have linked decisions.</p>|]
+                else forEach awaitingDecision renderAwaitingReq}
+        </div>
+
+        <!-- Recent decisions -->
+        <div class="bg-white rounded-lg border border-gray-200 px-6 py-5 mb-6">
+            <h2 class="text-sm font-semibold text-gray-700 mb-3">Recent Decisions</h2>
+            {if null recentDecisions
+                then [hsx|<p class="text-sm text-gray-400">No decisions recorded yet.</p>|]
+                else [hsx|
+                    <table class="w-full text-sm">
+                        <thead class="border-b border-gray-100">
+                            <tr>
+                                <th class="text-left py-2 text-xs font-medium text-gray-500">Title</th>
+                                <th class="text-left py-2 text-xs font-medium text-gray-500">Outcome</th>
+                                <th class="text-left py-2 text-xs font-medium text-gray-500">Source Widget</th>
+                                <th class="text-left py-2 text-xs font-medium text-gray-500">Decided At</th>
+                            </tr>
+                        </thead>
+                        <tbody class="divide-y divide-gray-50">
+                            {forEach recentDecisions (renderDecisionRow allRequirements allCandidates widgets)}
+                        </tbody>
+                    </table>
+                |]}
+        </div>
+
+        <!-- Traceability coverage per widget -->
+        <div class="bg-white rounded-lg border border-gray-200 px-6 py-5">
+            <h2 class="text-sm font-semibold text-gray-700 mb-3">Traceability Coverage</h2>
+            <table class="w-full text-sm">
+                <thead class="border-b border-gray-100">
+                    <tr>
+                        <th class="text-left py-2 text-xs font-medium text-gray-500">Widget</th>
+                        <th class="text-center py-2 text-xs font-medium text-gray-500">Annotation</th>
+                        <th class="text-center py-2 text-xs font-medium text-gray-500">Candidate</th>
+                        <th class="text-center py-2 text-xs font-medium text-gray-500">Decision</th>
+                    </tr>
+                </thead>
+                <tbody class="divide-y divide-gray-50">
+                    {forEach widgets (renderCoverageRow allAnnotations allCandidates allRequirements allDecisions)}
+                </tbody>
+            </table>
+        </div>
+    |]
+  where
+    awaitingDecision = filter (isAwaitingDecision allDecisions) allRequirements
+
+outcomeList :: [Text]
+outcomeList = ["accepted", "rejected", "deferred", "split", "merged", "reframed"]
+
+countOutcome :: [DecisionRecord] -> Text -> Int
+countOutcome decisions o = length (filter (\d -> d.outcome == o) decisions)
+
+renderKpiCard :: Text -> Int -> Html
+renderKpiCard outcome count = [hsx|
+    <div class={kpiCardClass outcome <> " rounded-lg px-4 py-3 text-center"}>
+        <div class="text-2xl font-bold">{show count}</div>
+        <div class="text-xs mt-0.5 opacity-75">{outcome}</div>
+    </div>
+|]
+
+kpiCardClass :: Text -> Text
+kpiCardClass "accepted"  = "bg-green-50 text-green-800"
+kpiCardClass "rejected"  = "bg-red-50 text-red-800"
+kpiCardClass "deferred"  = "bg-gray-50 text-gray-700"
+kpiCardClass "split"     = "bg-purple-50 text-purple-800"
+kpiCardClass "merged"    = "bg-indigo-50 text-indigo-800"
+kpiCardClass "reframed"  = "bg-orange-50 text-orange-800"
+kpiCardClass _           = "bg-gray-50 text-gray-700"
+
+isAwaitingDecision :: [DecisionRecord] -> Requirement -> Bool
+isAwaitingDecision decisions req =
+    not (any (\d -> d.requirementId == Just req.id) decisions)
+
+renderAwaitingReq :: Requirement -> Html
+renderAwaitingReq req = [hsx|
+    <div class="flex items-center justify-between py-2 border-b border-gray-50 last:border-0">
+        <a href={ShowRequirementAction { requirementId = req.id }}
+           class="text-sm text-indigo-600 hover:text-indigo-800">{req.title}</a>
+        <span class="text-xs text-gray-400">{show req.createdAt}</span>
+    </div>
+|]
+
+renderDecisionRow :: [Requirement] -> [RequirementCandidate] -> [Widget] -> DecisionRecord -> Html
+renderDecisionRow reqs candidates widgets dr = [hsx|
+    <tr>
+        <td class="py-2 pr-4">
+            <a href={ShowDecisionRecordAction { decisionRecordId = dr.id }}
+               class="text-indigo-600 hover:text-indigo-800">{dr.title}</a>
+        </td>
+        <td class="py-2 pr-4">
+            <span class={outcomeClass dr.outcome <> " text-xs px-2 py-0.5 rounded font-medium"}>
+                {dr.outcome}
+            </span>
+        </td>
+        <td class="py-2 pr-4 text-gray-600 text-xs">
+            {originWidget dr reqs candidates widgets}
+        </td>
+        <td class="py-2 text-gray-400 text-xs">{show dr.decidedAt}</td>
+    </tr>
+|]
+
+-- Trace decision → requirement → candidate → widget name
+originWidget :: DecisionRecord -> [Requirement] -> [RequirementCandidate] -> [Widget] -> Text
+originWidget dr reqs candidates widgets =
+    case dr.requirementId >>= \rid -> find (\r -> r.id == rid) reqs of
+        Just req ->
+            case find (\c -> c.id == req.sourceCandidateId) candidates of
+                Just c ->
+                    case find (\w -> w.id == c.sourceWidgetId) widgets of
+                        Just w  -> w.name
+                        Nothing -> "—"
+                Nothing -> "—"
+        Nothing ->
+            case dr.candidateId >>= \cid -> find (\c -> c.id == cid) candidates of
+                Just c ->
+                    case find (\w -> w.id == c.sourceWidgetId) widgets of
+                        Just w  -> w.name
+                        Nothing -> "—"
+                Nothing -> "—"
+
+renderCoverageRow :: [Annotation] -> [RequirementCandidate] -> [Requirement] -> [DecisionRecord] -> Widget -> Html
+renderCoverageRow annotations candidates requirements decisions w = [hsx|
+    <tr>
+        <td class="py-2 pr-4 text-sm text-gray-700">{w.name}</td>
+        <td class="py-2 text-center">{coverageMark hasAnnotation}</td>
+        <td class="py-2 text-center">{coverageMark hasCandidate}</td>
+        <td class="py-2 text-center">{coverageMark hasDecision}</td>
+    </tr>
+|]
+  where
+    hasAnnotation = any (\a -> a.widgetId == w.id) annotations
+    widgetCandidates = filter (\c -> c.sourceWidgetId == w.id) candidates
+    hasCandidate = not (null widgetCandidates)
+    candidateIds = map (.id) widgetCandidates
+    widgetReqIds = map (.id) (filter (\r -> r.sourceCandidateId `elem` candidateIds) requirements)
+    hasDecision  = any (\d -> d.requirementId `elem` map Just widgetReqIds) decisions
+
+coverageMark :: Bool -> Html
+coverageMark True  = [hsx|<span class="text-green-600 font-bold">✓</span>|]
+coverageMark False = [hsx|<span class="text-gray-300">✗</span>|]
+
+outcomeClass :: Text -> Text
+outcomeClass "accepted"  = "bg-green-100 text-green-800"
+outcomeClass "rejected"  = "bg-red-100 text-red-800"
+outcomeClass "deferred"  = "bg-gray-100 text-gray-600"
+outcomeClass "split"     = "bg-purple-100 text-purple-800"
+outcomeClass "merged"    = "bg-indigo-100 text-indigo-800"
+outcomeClass "reframed"  = "bg-orange-100 text-orange-800"
+outcomeClass _           = "bg-gray-100 text-gray-600"

Web/View/Hubs/Show.hs

@@ -33,6 +33,10 @@ instance View ShowView where
                        class="text-sm border border-indigo-300 text-indigo-700 px-3 py-1.5 rounded hover:bg-indigo-50">
                         Triage Dashboard
                     </a>
+                    <a href={GovernanceDashboardAction { hubId = hub.id }}
+                       class="text-sm border border-purple-300 text-purple-700 px-3 py-1.5 rounded hover:bg-purple-50">
+                        Governance Dashboard
+                    </a>
                     <a href={EditHubAction { hubId = hub.id }}
                        class="text-sm border border-gray-300 px-3 py-1.5 rounded hover:bg-gray-50">
                         Edit

Web/View/RequirementCandidates/Show.hs

@@ -67,6 +67,9 @@ instance View ShowView where
                 {renderReviewerSection candidate mAssignment users}
             </div>
 
+            <!-- Phase 3: Promote to Requirement / Link to Decision -->
+            {renderGovernanceActions candidate}
+
             <!-- Triage history -->
             <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
                 <h2 class="text-sm font-semibold text-gray-700 mb-3">Triage History</h2>
@@ -167,6 +170,51 @@ renderTriageRow ts = [hsx|
     </li>
 |]
 
+renderGovernanceActions :: RequirementCandidate -> Html
+renderGovernanceActions candidate
+    | candidate.status == "accepted" = [hsx|
+        <div class="bg-white rounded-lg border border-indigo-200 px-6 py-4">
+            <h2 class="text-sm font-semibold text-gray-700 mb-3">Governance</h2>
+            <div class="flex flex-wrap gap-3">
+                {renderPromoteButton candidate}
+                {renderLinkDecisionButton candidate}
+            </div>
+        </div>
+    |]
+    | otherwise = mempty
+
+renderPromoteButton :: RequirementCandidate -> Html
+renderPromoteButton candidate =
+    case candidate.requirementId of
+        Just rid -> [hsx|
+            <a href={ShowRequirementAction { requirementId = rid }}
+               class="text-sm text-green-700 bg-green-50 border border-green-200 px-3 py-1.5 rounded hover:bg-green-100">
+                Requirement →
+            </a>
+        |]
+        Nothing -> [hsx|
+            <form method="POST"
+                  action={PromoteToRequirementAction { requirementCandidateId = candidate.id }}>
+                {hiddenField "authenticity_token"}
+                <button type="submit"
+                        class="text-sm bg-indigo-600 text-white px-3 py-1.5 rounded hover:bg-indigo-700">
+                    Promote to Requirement
+                </button>
+            </form>
+        |]
+
+renderLinkDecisionButton :: RequirementCandidate -> Html
+renderLinkDecisionButton candidate = [hsx|
+    <form method="POST"
+          action={LinkToDecisionAction { requirementCandidateId = candidate.id }}>
+        {hiddenField "authenticity_token"}
+        <button type="submit"
+                class="text-sm bg-gray-700 text-white px-3 py-1.5 rounded hover:bg-gray-800">
+            Create Decision Record
+        </button>
+    </form>
+|]
+
 statusClass :: Text -> Text
 statusClass "open"      = "bg-blue-100 text-blue-700"
 statusClass "in_review" = "bg-yellow-100 text-yellow-800"

Web/View/Requirements/Index.hs

@@ -0,0 +1,69 @@
+module Web.View.Requirements.Index where
+
+import Web.Types
+import Generated.Types
+import IHP.Prelude
+import IHP.ViewPrelude
+
+data IndexView = IndexView
+    { requirements :: ![Requirement]
+    , candidates   :: ![RequirementCandidate]
+    }
+
+instance View IndexView where
+    html IndexView { .. } = [hsx|
+        <div class="flex items-center justify-between mb-6">
+            <h1 class="text-2xl font-semibold">Requirements</h1>
+        </div>
+        {if null requirements
+            then [hsx|<p class="text-sm text-gray-400">No requirements yet. Promote an accepted candidate to create one.</p>|]
+            else renderTable requirements candidates}
+    |]
+
+renderTable :: [Requirement] -> [RequirementCandidate] -> Html
+renderTable reqs candidates = [hsx|
+    <div class="bg-white rounded-lg border border-gray-200 overflow-hidden">
+        <table class="w-full text-sm">
+            <thead class="bg-gray-50 border-b border-gray-200">
+                <tr>
+                    <th class="text-left px-4 py-3 font-medium text-gray-600">Title</th>
+                    <th class="text-left px-4 py-3 font-medium text-gray-600">Status</th>
+                    <th class="text-left px-4 py-3 font-medium text-gray-600">Source Candidate</th>
+                    <th class="text-left px-4 py-3 font-medium text-gray-600">Created</th>
+                </tr>
+            </thead>
+            <tbody class="divide-y divide-gray-100">
+                {forEach reqs (renderRow candidates)}
+            </tbody>
+        </table>
+    </div>
+|]
+
+renderRow :: [RequirementCandidate] -> Requirement -> Html
+renderRow candidates req = [hsx|
+    <tr class="hover:bg-gray-50">
+        <td class="px-4 py-3">
+            <a href={ShowRequirementAction { requirementId = req.id }}
+               class="text-indigo-600 hover:text-indigo-800 font-medium">{req.title}</a>
+        </td>
+        <td class="px-4 py-3">
+            <span class={reqStatusClass req.status <> " text-xs px-2 py-0.5 rounded font-medium"}>
+                {req.status}
+            </span>
+        </td>
+        <td class="px-4 py-3 text-gray-600">
+            {candidateTitle candidates req.sourceCandidateId}
+        </td>
+        <td class="px-4 py-3 text-gray-400 text-xs">{show req.createdAt}</td>
+    </tr>
+|]
+
+candidateTitle :: [RequirementCandidate] -> Id RequirementCandidate -> Text
+candidateTitle cs cid =
+    maybe "(unknown)" (.title) (find (\c -> c.id == cid) cs)
+
+reqStatusClass :: Text -> Text
+reqStatusClass "active"     = "bg-green-100 text-green-800"
+reqStatusClass "superseded" = "bg-yellow-100 text-yellow-800"
+reqStatusClass "withdrawn"  = "bg-gray-100 text-gray-500"
+reqStatusClass _            = "bg-gray-100 text-gray-600"

Web/View/Requirements/Show.hs

@@ -0,0 +1,72 @@
+module Web.View.Requirements.Show where
+
+import Web.Types
+import Generated.Types
+import IHP.Prelude
+import IHP.ViewPrelude
+
+data ShowView = ShowView
+    { requirement :: !Requirement
+    , candidate   :: !RequirementCandidate
+    , widget      :: !Widget
+    , mDecision   :: !(Maybe DecisionRecord)
+    }
+
+instance View ShowView where
+    html ShowView { .. } = [hsx|
+        <div class="mb-6 flex items-center gap-2 text-sm text-gray-500">
+            <a href={RequirementsAction} class="hover:text-gray-700">Requirements</a>
+            <span>/</span>
+            <span>{requirement.title}</span>
+        </div>
+
+        <div class="max-w-3xl space-y-6">
+            <!-- Header card -->
+            <div class="bg-white rounded-lg border border-gray-200 px-6 py-5">
+                <div class="flex items-start justify-between mb-3">
+                    <h1 class="text-2xl font-semibold">{requirement.title}</h1>
+                    <span class={reqStatusClass requirement.status <> " text-xs px-2 py-0.5 rounded font-medium ml-4"}>
+                        {requirement.status}
+                    </span>
+                </div>
+                <p class="text-sm text-gray-700 leading-relaxed">{requirement.description}</p>
+            </div>
+
+            <!-- Source candidate -->
+            <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
+                <h2 class="text-sm font-semibold text-gray-700 mb-2">Source Candidate</h2>
+                <a href={ShowRequirementCandidateAction { requirementCandidateId = candidate.id }}
+                   class="text-sm text-indigo-600 hover:text-indigo-800">{candidate.title}</a>
+                <p class="text-xs text-gray-400 mt-1">Widget: {widget.name}</p>
+            </div>
+
+            <!-- Linked decision -->
+            <div class="bg-white rounded-lg border border-gray-200 px-6 py-4">
+                <h2 class="text-sm font-semibold text-gray-700 mb-2">Linked Decision</h2>
+                {case mDecision of
+                    Nothing -> [hsx|<p class="text-sm text-gray-400">No decision linked yet.</p>|]
+                    Just dr -> [hsx|
+                        <a href={ShowDecisionRecordAction { decisionRecordId = dr.id }}
+                           class="text-sm text-indigo-600 hover:text-indigo-800">{dr.title}</a>
+                        <span class={outcomeClass dr.outcome <> " text-xs px-2 py-0.5 rounded font-medium ml-2"}>
+                            {dr.outcome}
+                        </span>
+                    |]}
+            </div>
+        </div>
+    |]
+
+reqStatusClass :: Text -> Text
+reqStatusClass "active"     = "bg-green-100 text-green-800"
+reqStatusClass "superseded" = "bg-yellow-100 text-yellow-800"
+reqStatusClass "withdrawn"  = "bg-gray-100 text-gray-500"
+reqStatusClass _            = "bg-gray-100 text-gray-600"
+
+outcomeClass :: Text -> Text
+outcomeClass "accepted"  = "bg-green-100 text-green-800"
+outcomeClass "rejected"  = "bg-red-100 text-red-800"
+outcomeClass "deferred"  = "bg-gray-100 text-gray-600"
+outcomeClass "split"     = "bg-purple-100 text-purple-800"
+outcomeClass "merged"    = "bg-indigo-100 text-indigo-800"
+outcomeClass "reframed"  = "bg-orange-100 text-orange-800"
+outcomeClass _           = "bg-gray-100 text-gray-600"