Label key-collision lifecycle events in the finding timeline

Completes the deferred UI half of dad1152fc: the content_replaced
lifecycle event (emitted when a same-key re-detection's text is
substantially different from the existing finding — a key collision)
now renders as "Re-detected with different details" in the finding
timeline instead of the identifier-formatter fallback, so the operator
reads what actually happened in plain language. The event metadata
already carries the previous and new titles.

Ceremony this line deferred from the backend commit: patrol-intelligence
contract Current State entry (lifecycle label map rule + the new label),
ai-runtime cross-reference updated, and the label pinned in
FindingsPanel.test.ts lifecycleLabels (the subsystem's accepted proof).
111 FindingsPanel tests green.

docs/release-control/v6/internal/subsystems/ai-runtime.md

@@ -2343,10 +2343,8 @@ old issue: both `content_replaced` and `regressed` events appear).
 Rephrasings and identical re-detections stay event-free per the
 heartbeat-not-transition rule. The shared lifecycle presentation
 (`frontend-modern/src/utils/aiFindingPresentation.ts`,
-patrol-intelligence subsystem) renders unknown lifecycle types through the
-identifier-formatter fallback, so the event reads "Content replaced" today;
-a dedicated label is patrol-intelligence UI work and lands with that
-subsystem's own ceremony.
+patrol-intelligence subsystem) labels the event "Re-detected with different
+details" — see that contract's Current State entry for the UI-side rule.
 `TestFindingsStore_KeyCollisionRecordsContentReplacedEvent` and its
 companion tests (`internal/ai/findings_lifecycle_test.go`) pin the behavior.
 

docs/release-control/v6/internal/subsystems/patrol-intelligence.md

@@ -434,6 +434,18 @@ Patrol-specific presentation helpers.
 
 ## Current State
 
+The finding lifecycle timeline renders backend lifecycle event types through
+the shared label map in
+`frontend-modern/src/utils/aiFindingPresentation.ts`
+(`formatFindingLifecycleType`), with unknown types falling back to the
+identifier formatter. The `content_replaced` event — emitted by the
+ai-runtime findings store when a same-key re-detection's text is
+substantially different from the existing finding (a key collision; see the
+ai-runtime contract's Current State entry) — is labeled "Re-detected with
+different details" so the operator timeline explains the shift in plain
+language; the event's metadata carries the previous and new titles.
+`FindingsPanel.test.ts` (`lifecycleLabels`) pins the label.
+
 The Patrol findings panel
 (`frontend-modern/src/components/AI/FindingsPanel.tsx`) dropped its "Open
 related infrastructure / workloads / storage / recovery" cross-jump chip

frontend-modern/src/components/AI/__tests__/FindingsPanel.test.ts

@@ -1000,6 +1000,16 @@ describe('aiFindingPresentation', () => {
     it('has dismissed label', () => {
       expect(formatFindingLifecycleType('dismissed')).toBe('Dismissed');
     });
+
+    it('labels a key-collision content replacement as a re-detection with different details', () => {
+      // Backend emits content_replaced when a same-key re-detection's text
+      // is substantially different from the existing finding (a key
+      // collision); the timeline label must explain the shift in operator
+      // language rather than the raw identifier fallback.
+      expect(formatFindingLifecycleType('content_replaced')).toBe(
+        'Re-detected with different details',
+      );
+    });
   });
 
   describe('formatLifecycleType', () => {

frontend-modern/src/utils/aiFindingPresentation.ts

@@ -109,6 +109,7 @@ const FINDING_LIFECYCLE_LABELS: Record<string, string> = {
   loop_state: 'Loop state changed',
   seen_while_suppressed: 'Seen while suppressed',
   loop_transition_violation: 'Invalid transition blocked',
+  content_replaced: 'Re-detected with different details',
 };
 
 const FINDING_STATUS_BADGE_CLASSES: Record<string, string> = {