[claude] App-state aware WebSocket reconnect on foreground (#33) (#77)

artifacts/mobile/context/TimmyContext.tsx

@@ -7,6 +7,7 @@ import React, {
   useRef,
   useState,
 } from "react";
+import { AppState, Platform } from "react-native";
 
 export type TimmyMood = "idle" | "thinking" | "working" | "speaking";
 
@@ -21,7 +22,7 @@ export type WsEvent = {
   count?: number;
 };
 
-export type ConnectionStatus = "connecting" | "connected" | "disconnected" | "error";
+export type ConnectionStatus = "connecting" | "connected" | "disconnected" | "reconnecting" | "error";
 
 type TimmyContextValue = {
   timmyMood: TimmyMood;
@@ -215,6 +216,54 @@ export function TimmyProvider({ children }: { children: React.ReactNode }) {
     };
   }, [connectWs]);
 
+  // AppState-aware WebSocket reconnect on foreground
+  useEffect(() => {
+    if (Platform.OS === "web") return;
+
+    const appStateRef = { current: AppState.currentState };
+
+    const subscription = AppState.addEventListener("change", (nextAppState) => {
+      const wasBackground =
+        appStateRef.current === "background" ||
+        appStateRef.current === "inactive";
+      const isNowActive = nextAppState === "active";
+
+      if (wasBackground && isNowActive) {
+        // App returned to foreground — check if WS is still alive
+        const ws = wsRef.current;
+        if (!ws || ws.readyState !== WebSocket.OPEN) {
+          // Cancel any pending retry so we don't create duplicates
+          if (retryTimerRef.current) {
+            clearTimeout(retryTimerRef.current);
+            retryTimerRef.current = null;
+          }
+          retryCountRef.current = 0;
+          setConnectionStatus("reconnecting");
+          connectWs();
+        }
+      } else if (nextAppState === "background") {
+        // Proactively close the WS to avoid OS killing it mid-frame
+        if (retryTimerRef.current) {
+          clearTimeout(retryTimerRef.current);
+          retryTimerRef.current = null;
+        }
+        if (wsRef.current) {
+          wsRef.current.onclose = null;
+          wsRef.current.onerror = null;
+          wsRef.current.close();
+          wsRef.current = null;
+        }
+        setConnectionStatus("disconnected");
+      }
+
+      appStateRef.current = nextAppState;
+    });
+
+    return () => {
+      subscription.remove();
+    };
+  }, [connectWs]);
+
   const send = useCallback((msg: object) => {
     if (wsRef.current && wsRef.current.readyState === WebSocket.OPEN) {
       wsRef.current.send(JSON.stringify(msg));