fix(collab): fix self-lockout, stuck live sessions, block locking propagation and reactive hashtags

internal/ws/hub.go

@@ -644,6 +644,17 @@ func (h *Hub) EndLiveSession(docID, userID string) bool {
 	return true
 }
 
+func (h *Hub) ForceEndLiveSession(docID string) bool {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+
+	if _, exists := h.liveSessions[docID]; !exists {
+		return false
+	}
+	delete(h.liveSessions, docID)
+	return true
+}
+
 func (h *Hub) GetLiveSession(docID string) *domain.LiveSessionInfo {
 	h.mu.RLock()
 	defer h.mu.RUnlock()