feat: centralized PTY-scoped session state, sync engine debug panel, lifecycle states, WS monitor

- Refactor session state to use ptySessionId as primary key across all components
- Add SessionStateManager with PTY-scoped hook processing, approval tracking, notifications
- Add sync-engine debug panel (AgentStatesSection, HookTimelineSection, TerminalRegistrySection, WsMonitorSection)
- Add useLifecycleStates composable for continuous state chips (session, responding, tool, subagent, compacting)
- Add WS monitor endpoint and composable for real-time connection health
- Enhance SessionLifecycleStatus with animated state chips and badge counts
- Enhance SystemMessage with expanded content and better formatting
- Update hooks (approval-permission, approval-plan, notify) with pty_session injection
- Update approval system to derive pending lists from PTY-scoped state
- Update ChatContainer with PTY-derived agent status and lifecycle events
- Update AgentBadge with PTY-scoped status colors
- Improve PiP window, approval window, and loading window handling

hooks/approval-plan.ps1

@@ -15,9 +15,14 @@ if ($j.permission_mode -ne 'plan' -or $j.stop_hook_active) {
   Add-Content $logFile "[$ts] [PLAN] Skipping (not plan mode or stop_hook_active)"
   exit 0
 }
+$url = 'http://localhost:4101/api/hooks-approval/plan'
+$sep = '?'
+$pty = $env:AGENT_UI_PTY_SESSION
+if ($pty) { $url += "${sep}pty_session=$pty"; $sep = '&' }
+if ($agent -and $agent -ne 'local') { $url += "${sep}agent=$agent" }
 try {
   Add-Content $logFile "[$ts] [PLAN] POSTing to backend..."
-  $r = Invoke-RestMethod -Uri 'http://localhost:4101/api/hooks-approval/plan' -Method POST -Body $b -ContentType 'application/json' -TimeoutSec 125
+  $r = Invoke-RestMethod -Uri $url -Method POST -Body $b -ContentType 'application/json' -TimeoutSec 125
   $ts2 = Get-Date -Format "HH:mm:ss.fff"
   if ($r -and $r.decision) {
     $out = $r | ConvertTo-Json -Depth 10 -Compress