Simplify reconnect handlers and fix connect_error overlay flicker

- Merge handleOnline and the shared branch of handleVisibilityChange into a
  single handleReturn function. visibilitychange is now a thin guard that calls
  it only on show. Both events share the same logic: reconnect if socket dropped,
  or restore UI state + rejoin room + revalidate if the socket survived.

- Remove setIsReconnecting(false) from connect_error: reconnect_attempt fires
  immediately after and resets it to true anyway, causing the "Reconnecting"
  overlay to flicker off and back on during every retry cycle.

https://claude.ai/code/session_016tCZVFjSeHdQsdKktbDHEt

app/hooks/useDraftSocket.ts

@@ -57,7 +57,8 @@ export function useDraftSocket(seasonId: string, teamId?: string): UseDraftSocke
     socket.on("connect_error", (error) => {
       console.error("Socket.IO connection error:", error);
       setConnectionError(error.message || "Failed to connect to draft server");
-      setIsReconnecting(false);
+      // Don't clear isReconnecting here — reconnect_attempt fires immediately
+      // after and sets it back to true, causing a visible flicker in the overlay.
     });
 
     socket.io.on("reconnect_attempt", () => {
@@ -75,48 +76,40 @@ export function useDraftSocket(seasonId: string, teamId?: string): UseDraftSocke
     const handleOffline = () => {
       // Mark as reconnecting immediately — the OS fires this before Socket.IO's
       // heartbeat would detect the drop (~15s later). Note: "offline" can fire
-      // spuriously on mobile; handleOnline corrects the state if the socket is
+      // spuriously on mobile; handleReturn corrects the state if the socket is
       // still alive when the network returns.
       setIsConnected(false);
       setIsReconnecting(true);
     };
 
-    const handleOnline = () => {
+    // Unified handler for both "network returned" (online event) and
-      if (socketRef.current?.connected) {
+    // "browser tab/app regained focus" (visibilitychange). Two cases:
-        // Network blipped but the socket stayed alive (came back within ping timeout window).
+    //   - Socket dropped: reconnect immediately, bypassing backoff.
-        // The socket never disconnected so no "connect" event will fire — correct UI directly.
+    //   - Socket alive: restore UI state and rejoin the draft room so the page
+    //     revalidates and picks up any events missed while the client was away.
+    const handleReturn = () => {
+      if (!socketRef.current?.connected) {
+        socketRef.current?.connect();
+      } else {
         setIsConnected(true);
         setIsReconnecting(false);
-      } else {
+        socketRef.current.emit("join-draft", seasonId, teamId);
-        // Genuinely disconnected — skip backoff and reconnect immediately.
-        socketRef.current?.connect();
-      }
-    };
-
-    const handleVisibilityChange = () => {
-      if (document.visibilityState !== "visible") return;
-
-      if (!socketRef.current?.connected) {
-        // Mobile browsers kill WebSockets when the app is backgrounded without
-        // firing "offline". Reconnect immediately when the user returns.
-        socketRef.current?.connect();
-      } else {
-        // Socket appears connected but may have gone stale while JS was suspended.
-        // Rejoin the draft room (idempotent) and bump reconnectCount so the draft
-        // page revalidates loader data to catch any picks/state changes missed
-        // while the browser was backgrounded.
-        socketRef.current?.emit("join-draft", seasonId, teamId);
         setReconnectCount((c) => c + 1);
       }
     };
 
+    // visibilitychange fires on both hide and show — only act on show.
+    const handleVisibilityChange = () => {
+      if (document.visibilityState === "visible") handleReturn();
+    };
+
     window.addEventListener("offline", handleOffline);
-    window.addEventListener("online", handleOnline);
+    window.addEventListener("online", handleReturn);
     document.addEventListener("visibilitychange", handleVisibilityChange);
 
     return () => {
       window.removeEventListener("offline", handleOffline);
-      window.removeEventListener("online", handleOnline);
+      window.removeEventListener("online", handleReturn);
       document.removeEventListener("visibilitychange", handleVisibilityChange);
       console.log("Leaving draft room:", seasonId);
       socket.emit("leave-draft", seasonId);