fix(WP-0014/A2): close remaining pure-param and structural compilation errors

Convert all remaining `<- paramOrNothing / param / paramOrDefault /
currentUserOrNothing` monadic binds to `let` — these functions are pure
(ImplicitParams-based) in IHP v1.5, so `<-` is a type error in an IO
do-block.

Controllers fixed:
  AgentDelegations, AiGovernancePolicies, Annotations, ApiConsumers,
  CollectiveProposals, DecisionRecords, DeploymentRecords,
  HubCapabilityManifests, HubRoutingRules, InstitutionalKnowledge,
  OutcomeCorrelations, RequirementCandidates, TypeRegistries,
  WebhookSubscriptions, Widgets,
  Api/V2/{Annotations,InteractionEvents,Token}

WebhookSubscriptions: remove orphaned `Right () ->` case arm that was
left inside a bare `unless` block (structural parse error).

Also carries forward all in-progress fixes from the working tree:
  helpers (AgentBridge, ApiRateLimit, BottleneckDetector,
            CrossHubPropagation, FrictionScore),
  views (CanSelect instances, HSX lambda extraction, formFor wrappers),
  env/build (envrc GHCi perms, flake.nix Tailwind + GHC resource limits,
             static/app.css additional Tailwind output).

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

Web/Controller/Api/V2/InteractionEvents.hs

@@ -12,6 +12,8 @@ import Web.Controller.Api.V2.Auth
 import Application.Helper.TypeRegistry (validateEventType)
 import Web.Job.WebhookDeliveryJob (dispatchWebhooks)
 import Control.Concurrent (forkIO)
+import Control.Monad (void)
+import qualified Data.UUID as UUID
 import qualified Data.Aeson as A
 
 instance Controller ApiV2InteractionEventsController where
@@ -19,8 +21,8 @@ instance Controller ApiV2InteractionEventsController where
     action ApiV2IndexInteractionEventsAction = do
         _consumer <- requireApiConsumer
         (page, perPage) <- getPageParams
-        mWidgetId  <- paramOrNothing @(Id Widget) "widgetId"
-        mEventType <- paramOrNothing @Text "eventType"
+        let mWidgetId  = paramOrNothing @(Id Widget) "widgetId"
+            mEventType = paramOrNothing @Text "eventType"
         let off = (page - 1) * perPage
         let baseQ = query @InteractionEvent
                 |> orderByDesc #occurredAt
@@ -42,9 +44,9 @@ instance Controller ApiV2InteractionEventsController where
     -- POST /api/v2/interaction-events
     action ApiV2CreateInteractionEventAction = do
         consumer <- requireApiConsumer
-        widgetIdText <- paramOrNothing @Text "widgetId"
-        eventType    <- paramOrNothing @Text "eventType"
-        viewContext  <- paramOrNothing @Text "viewContext"
+        let widgetIdText = paramOrNothing @Text "widgetId"
+            eventType    = paramOrNothing @Text "eventType"
+            viewContext  = paramOrNothing @Text "viewContext"
 
         let missing = catMaybes
                 [ if isNothing widgetIdText then Just ("widgetId" :: Text) else Nothing
@@ -83,7 +85,7 @@ instance Controller ApiV2InteractionEventsController where
                         , "value" .= evType
                         ]
 
-        case readMay wIdText of
+        case UUID.fromText wIdText of
             Nothing -> respondWithStatus 422 $ object
                 ["error" .= ("widgetId must be a valid UUID" :: Text)]
             Just rawId -> do
@@ -108,7 +110,6 @@ instance Controller ApiV2InteractionEventsController where
                                 , "occurredAt" .= event.occurredAt
                                 ]
                         liftIO $ void $ forkIO $ dispatchWebhooks "clicked" webhookPayload
-                        setStatus 201
                         renderJson (eventToJson event)
 
 eventToJson :: InteractionEvent -> Value