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/Index.hs

@@ -0,0 +1,108 @@
+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"