fix(collab): fix corporate SSE fallback, realtime lock propagation and prevent stale overwrite

internal/api/server.go

@@ -861,11 +861,18 @@ func (s *Server) broadcastDocToAuthorizedUsers(docID, event string) {
 	if err != nil {
 		return
 	}
+	var firstDoc *domain.Document
 	for _, uid := range users {
 		if userDoc, err := s.store.GetDocumentByID(uid, docID); err == nil && userDoc != nil {
+			if firstDoc == nil {
+				firstDoc = userDoc
+			}
 			s.wsHub.BroadcastToUser(uid, event, userDoc)
 		}
 	}
+	if s.wsHub != nil && firstDoc != nil {
+		s.wsHub.BroadcastRoom("doc:"+docID, event, firstDoc, nil)
+	}
 }
 
 func (s *Server) handleGetDocuments(w http.ResponseWriter, r *http.Request) {
@@ -1516,16 +1523,18 @@ func (s *Server) handleUnlockBlock(w http.ResponseWriter, r *http.Request) {
 	blockID := chi.URLParam(r, "blockId")
 
 	if s.wsHub != nil {
-		s.wsHub.ReleaseBlockLock(docID, blockID, userID)
-		evt := map[string]string{
-			"docId":   docID,
-			"blockId": blockID,
-			"userId":  userID,
-		}
-		s.wsHub.BroadcastRoom("doc:"+docID, "DOC_BLOCK_UNLOCKED", evt, nil)
-		if users, err := s.store.GetAuthorizedDocUsers(docID); err == nil {
-			for _, uid := range users {
-				s.wsHub.BroadcastToUser(uid, "DOC_BLOCK_UNLOCKED", evt)
+		released := s.wsHub.ReleaseBlockLock(docID, blockID, userID)
+		if released {
+			evt := map[string]string{
+				"docId":   docID,
+				"blockId": blockID,
+				"userId":  userID,
+			}
+			s.wsHub.BroadcastRoom("doc:"+docID, "DOC_BLOCK_UNLOCKED", evt, nil)
+			if users, err := s.store.GetAuthorizedDocUsers(docID); err == nil {
+				for _, uid := range users {
+					s.wsHub.BroadcastToUser(uid, "DOC_BLOCK_UNLOCKED", evt)
+				}
 			}
 		}
 	}