feat: implement 11 new hooks for phases 21-22, v1.4-v1.6 (83 new tests)

- Phase 21: useDevOpsAgent, useCodeGen, usePredictive (spec/ai gaps)
- Phase 22: useETLPipeline, useConnector (spec/automation + integration gaps)
- v1.4: useNotificationCenter (activity feed, priority, filters, bulk)
- v1.5: useMessaging, useChannels (DMs, threads, reactions, channels)
- v1.6: useSelectiveSync, useConflictResolution, useOfflineAnalytics
- All hooks exported from barrel (hooks/useObjectStack.ts)
- 1003 tests passing (127 suites), TypeScript + ESLint clean

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Copilot

hooks/useObjectStack.ts

@@ -85,3 +85,24 @@ export { useDeepLink } from "./useDeepLink";
 export { useWidgetKit } from "./useWidgetKit";
 export { useVoiceShortcuts } from "./useVoiceShortcuts";
 export { useWatchConnectivity } from "./useWatchConnectivity";
+
+/* ---- Phase 21: Spec Gap — AI DevOps/CodeGen/Predictive ---- */
+export { useDevOpsAgent } from "./useDevOpsAgent";
+export { useCodeGen } from "./useCodeGen";
+export { usePredictive } from "./usePredictive";
+
+/* ---- Phase 22: Spec Gap — ETL & Connectors ---- */
+export { useETLPipeline } from "./useETLPipeline";
+export { useConnector } from "./useConnector";
+
+/* ---- v1.4: Notification Center ---- */
+export { useNotificationCenter } from "./useNotificationCenter";
+
+/* ---- v1.5: Messaging & Channels ---- */
+export { useMessaging } from "./useMessaging";
+export { useChannels } from "./useChannels";
+
+/* ---- v1.6: Advanced Offline ---- */
+export { useSelectiveSync } from "./useSelectiveSync";
+export { useConflictResolution } from "./useConflictResolution";
+export { useOfflineAnalytics } from "./useOfflineAnalytics";