feat(hooks): add pulse-monitor for token stall detection and auto-recovery

- Detect token stalls via message.part.updated heartbeat monitoring
- Support thinking/reasoning block detection with extended timeout
- Auto-recover: abort + 'continue' prompt on 5min stall
- Pause monitoring during tool execution

src/hooks/index.ts

@@ -4,3 +4,4 @@ export { createSessionNotification } from "./session-notification"
 export { createSessionRecoveryHook } from "./session-recovery"
 export { createCommentCheckerHooks } from "./comment-checker"
 export { createGrepOutputTruncatorHook } from "./grep-output-truncator"
+export { createPulseMonitorHook } from "./pulse-monitor"