refactor(app): simplify session directory with direct snapshots and add sessionReady state

Replace subscription-based session accessor pattern with direct snapshot updates in daemon connections context. Add sessionReady flag to connection state to track when initial agent list has been received. Auto-select first ready host in create agent modal. Migrate from app.json to app.config.js. Add android:release script and Playwright testing docs.

packages/app/src/hooks/use-websocket.ts

@@ -207,7 +207,10 @@ export function useWebSocket(url: string, conversationId?: string | null): UseWe
   }, []);
 
   const on = useCallback(
-    (type: SessionOutboundMessage["type"], handler: (message: SessionOutboundMessage) => void) => {
+    (
+      type: SessionOutboundMessage["type"],
+      handler: (message: SessionOutboundMessage) => void
+    ) => {
       if (!handlersRef.current.has(type)) {
         handlersRef.current.set(type, new Set());
       }