* fix(server): restore agent finish notifications after daemon restart
Finish observers lived only in memory, so a restarted daemon silently lost the wakeup parents relied on. Persist subscription intent through notification dispatch acknowledgment and reconcile local and remote children after bootstrap.
* fix(server): reject finish subscriptions for unsent remote prompts
Connection and snapshot preflight failures happen before remote prompt transmission. Reject those candidates while retaining ambiguous sends, and preserve the host identity in callbacks. Exercise local permission cycles and storage errors through MCP.
* fix(server): notify parents when remote finish observation is exhausted
Three failed observations or a removed registration consume the watch after the parent accepts dispatch. Report unknown child status, retain the captured outcome through delivery failures, and keep connecting attempts outside the failure budget.
* fix(server): describe exhausted child observation accurately
Remote RPC failures do not prove the host is offline. Report the failed observation and unknown child status, and give Windows integration polling more margin.