fix(realtime): eliminate cpu reconnect loop, singleton global connection & fix disappearing notes

internal/ws/hub.go

@@ -761,10 +761,11 @@ func (c *Client) readPump() {
 			break
 		}
 
-		// Handle client-initiated lock, CRDT, and presence messages
+		// Handle client-initiated lock, CRDT, room subscription, and presence messages
 		var incoming struct {
 			Event   string          `json:"event"`
 			DocID   string          `json:"docId"`
+			Room    string          `json:"room"`
 			Payload json.RawMessage `json:"payload"`
 		}
 		if json.Unmarshal(message, &incoming) == nil && c.userID != "" && c.userID != "anonymous" {
@@ -777,6 +778,25 @@ func (c *Client) readPump() {
 				docID = p.DocID
 			}
 
+			// Room subscription without requiring docID
+			if incoming.Event == "JOIN_ROOM" {
+				room := incoming.Room
+				if room == "" {
+					room = docID
+				}
+				if room != "" {
+					c.hub.JoinRoom(c, room)
+				}
+			} else if incoming.Event == "LEAVE_ROOM" {
+				room := incoming.Room
+				if room == "" {
+					room = docID
+				}
+				if room != "" {
+					c.hub.LeaveRoom(c, room)
+				}
+			}
+
 			if docID != "" {
 				switch incoming.Event {
 				case "LOCK_DOC":