feat(P4): IHF Phase 4 complete — Outcome Observation and Antifragility Loop

Closes the IHF improvement loop. Full antifragility chain now traversable:
Widget → Annotation → Candidate → Requirement → Decision → Deployment → OutcomeSignal

New artifacts:
- DeploymentRecord (immutable, links DecisionRecord to a deployed version)
- OutcomeSignal (append-only; DB trigger prevents UPDATE/DELETE)
- ChangeEvaluation (one-per-deployment; UNIQUE constraint; 1–5 score)

New capabilities:
- DeploymentRecordsController (index, show, new, create)
- RecordOutcomeSignalAction — capture improved/regressed/neutral/inconclusive signals
- Pre/post comparison panel on deployment show (±30-day event/annotation counts)
- Regression detection — improved signal followed by high/critical annotation
- ChangeEvaluation — idempotent score+rationale per deployment
- Recurrence tracking — cycle count per widget, leaderboard
- AntifragilityDashboardAction (autoRefresh, 5 panels) per hub
- Phase 4 integration tests (T01–T08 logic coverage)
- docs/phase4-summary.md; SCOPE.md updated to Phase 4 complete

State Hub: workstream 07e9c860 → completed

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

workplans/IHUB-WP-0004-ihf-phase4-outcome-observation-and-antifragility.md

@@ -4,7 +4,7 @@ type: workplan
 title: "IHF Phase 4 — Outcome Observation and Antifragility Loop"
 domain: inter_hub
 repo: inter-hub
-status: active
+status: done
 owner: custodian
 topic_slug: inter_hub
 created: "2026-03-29"
@@ -69,7 +69,7 @@ Reference: `docs/ihp-overview.md`, `docs/ihp-data-and-queries.md`,
 
 ```task
 id: IHUB-WP-0004-T01
-status: todo
+status: done
 priority: high
 state_hub_task_id: "4d0aa6d5-f291-4053-a487-8c64627f8271"
 ```
@@ -149,7 +149,7 @@ CREATE INDEX change_evaluations_deployment_id_idx ON change_evaluations (deploym
 
 ```task
 id: IHUB-WP-0004-T02
-status: todo
+status: done
 priority: high
 state_hub_task_id: "4932b036-fe91-4146-9b35-7d3031894c2d"
 ```
@@ -175,7 +175,7 @@ full decision → requirement → widget chain.
 
 ```task
 id: IHUB-WP-0004-T03
-status: todo
+status: done
 priority: high
 state_hub_task_id: "8b39bbb3-4129-4acc-97ac-38ecfcfd7c88"
 ```
@@ -202,7 +202,7 @@ append-only constraint verified; color roles applied consistently.
 
 ```task
 id: IHUB-WP-0004-T04
-status: todo
+status: done
 priority: high
 state_hub_task_id: "27c4de52-755a-40e7-bef3-986fe4470f7c"
 ```
@@ -226,7 +226,7 @@ direction color-coded correctly; works with no post-deployment data (shows "—"
 
 ```task
 id: IHUB-WP-0004-T05
-status: todo
+status: done
 priority: high
 state_hub_task_id: "844a828b-b7d7-4822-becc-b377c08c673a"
 ```
@@ -253,7 +253,7 @@ affected widgets; count accurate on dashboard.
 
 ```task
 id: IHUB-WP-0004-T06
-status: todo
+status: done
 priority: medium
 state_hub_task_id: "391c6136-baea-417a-9291-5ba9f633e03f"
 ```
@@ -275,7 +275,7 @@ correct color in all views.
 
 ```task
 id: IHUB-WP-0004-T07
-status: todo
+status: done
 priority: medium
 state_hub_task_id: "6a5eea23-4e73-441a-ab93-49f5b76bf3ea"
 ```
@@ -300,7 +300,7 @@ visible on widget show page.
 
 ```task
 id: IHUB-WP-0004-T08
-status: todo
+status: done
 priority: high
 state_hub_task_id: "e5c65c77-c757-49a6-a8e9-99c8d3503f59"
 ```
@@ -326,7 +326,7 @@ All five panels render with correct data.
 
 ```task
 id: IHUB-WP-0004-T09
-status: todo
+status: done
 priority: high
 state_hub_task_id: "1dda0a32-4913-4007-a9f4-1d86761a8cf1"
 ```