feat(core): enable socket cors (#12823)

fix android & ios selfhost syncing

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **Bug Fixes**
- Improved WebSocket connection compatibility by enabling cross-origin
requests with credentials and restricting allowed HTTP methods to GET
and POST.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Co-authored-by: fengmk2 <fengmk2@gmail.com>

packages/backend/server/src/base/websocket/adapter.ts

@@ -20,6 +20,12 @@ export class SocketIoAdapter extends IoAdapter {
     const server: Server = super.createIOServer(port, {
       ...config,
       ...options,
+      // Enable CORS for Socket.IO
+      cors: {
+        origin: true, // Allow all origins
+        credentials: true, // Allow credentials (cookies, auth headers)
+        methods: ['GET', 'POST'],
+      },
     });
 
     if (config.canActivate) {