Fix loading state bugs and server crash

Backend fixes:
- Fix server crash when logging large session_state messages (186 agents)
- Use safe logging that extracts only message/stack properties
- Prevents TypeError in util.inspect on circular refs or deep objects

Frontend loading state fixes:
- Add reactive WebSocket update to prevent stale session.ws references
- Add timeout/retry wrapper for session_state loading (3 retries × 15s)
- Add hasEverReceivedSessionState flag to track cached data across reconnects
- Implement data-aware loading (isInitialLoad vs isRevalidating)
- Show reconnecting badge instead of hiding agents on reconnect

Debug improvements:
- Add detailed connection state logging in useAggregatedAgents
- Add connection status logging in AgentInputArea
- Track connecting reasons for easier debugging

Fixes:
- Agent screen no longer shows false "Offline" toast on reconnect
- Home screen shows loading immediately (no empty state flash)
- Home screen keeps agents visible during reconnect with badge
- Stuck loading has timeout protection with graceful degradation
- Server no longer crashes when sending session_state with many agents

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

packages/app/src/stores/session-store.ts

@@ -247,6 +247,7 @@ interface SessionStoreActions {
   initializeSession: (serverId: string, ws: UseWebSocketReturn, audioPlayer: ReturnType<typeof useAudioPlayer>) => void;
   clearSession: (serverId: string) => void;
   getSession: (serverId: string) => SessionState | undefined;
+  updateSessionWebSocket: (serverId: string, ws: UseWebSocketReturn) => void;
 
   // Audio state
   setIsPlayingAudio: (serverId: string, playing: boolean) => void;
@@ -383,6 +384,37 @@ export const useSessionStore = create<SessionStore>()(
       });
     },
 
+    updateSessionWebSocket: (serverId, ws) => {
+      set((prev) => {
+        const session = prev.sessions[serverId];
+
+        if (!session) {
+          return prev;
+        }
+
+        if (session.ws === ws) {
+          return prev;
+        }
+
+        logSessionStoreUpdate("updateSessionWebSocket", serverId, {
+          wasNull: session.ws === null,
+          isNowConnected: ws.isConnected,
+          isNowConnecting: ws.isConnecting,
+        });
+
+        return {
+          ...prev,
+          sessions: {
+            ...prev.sessions,
+            [serverId]: {
+              ...session,
+              ws,
+            },
+          },
+        };
+      });
+    },
+
     getSession: (serverId) => {
       return get().sessions[serverId];
     },