fix: should now sync with other devices

agents-docs/features/authentication.md

@@ -52,7 +52,7 @@ Require `Authorization: Bearer`:
 ```
 
 - `oderId` must match the token's user id when provided.
-- `clientInstanceId` is a stable per-install UUID generated by the product client (`metoyou.clientInstanceId` in `localStorage`). The signaling server uses it to distinguish multiple WebSocket connections for the same user and to route voice ownership.
+- `clientInstanceId` is a stable per-tab UUID generated by the product client (`metoyou.clientInstanceId` in `sessionStorage`). The signaling server uses it to distinguish multiple WebSocket connections for the same user and to route voice ownership.
 - Server responds with `auth_error` or `auth_required` when authentication fails.
 
 ## Multi-device sessions
@@ -62,6 +62,39 @@ Require `Authorization: Bearer`:
 - Voice/WebRTC is exclusive per user: only one `clientInstanceId` may own active voice at a time. Other connections show passive UI and can send `voice_client_takeover` to move voice to the local device.
 - Stale reconnect hygiene: when a client re-identifies with the same `(oderId, connectionScope, clientInstanceId)` tuple, the server closes the older socket for that tuple.
 
+### Account-owned state sync (`account_sync`)
+
+When the same account is logged in on multiple devices, account-owned data is kept in sync through the signaling server:
+
+| Data | Mechanism |
+|---|---|
+| Server chat messages | Existing `chat_message` relay (connection-scoped broadcast) |
+| Voice / typing | Existing `voice_state` / `user_typing` relays |
+| Saved servers (join/leave) | `account_sync` payload `saved-room-sync` / `saved-room-remove` |
+| Profile avatar + card text | `account_sync` `user-avatar-full` + `user-avatar-chunk` |
+| Custom emoji library | `account_sync` `custom-emoji-full` + `custom-emoji-chunk` |
+| Friends list | `account_sync` `friend-added` / `friend-removed` |
+| Server icons, edits, reactions | `account_sync` relay of existing P2P broadcast event types |
+
+Client rules:
+
+- `broadcastMessage()` still fans out over peer data channels; relayable events are **also** wrapped in `account_sync` and sent on the WebSocket.
+- The server forwards `account_sync` to every other open connection for the same `oderId` via `notifyOtherConnectionsForOderId`.
+- Receivers ignore payloads whose `clientInstanceId` matches the local tab id.
+- When a new device identifies, the server notifies existing connections with `account_sync_peer_online`; those devices push a full snapshot (saved rooms, friends, profile, emoji library).
+
+WebSocket envelope:
+
+```json
+{
+  "type": "account_sync",
+  "clientInstanceId": "<per-tab-uuid>",
+  "payload": { "type": "saved-room-sync", "room": { "...": "..." } }
+}
+```
+
+Server response to other connections includes `fromUserId` set to the sender's `oderId`.
+
 ## Client storage
 
 The product client stores tokens per signaling-server base URL in `localStorage` (`metoyou.authTokens`). An HTTP interceptor attaches the bearer token to `/api/*` requests targeting that server.