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

frontend/src/features/workspace/OutlinerTree.tsx

@@ -329,7 +329,7 @@ export const OutlinerTree: React.FC<OutlinerTreeProps> = ({
     <div className="space-y-0.5">
       {visibleEntries.map(({ block, index, hasChildren, maxAllowedLevel }) => {
         const lockInfo = activeBlockLocks?.[block.id];
-        const isLockedByOther = Boolean(lockInfo && lockInfo.userId !== currentUserId);
+        const isLockedByOther = Boolean(lockInfo && currentUserId && lockInfo.userId !== currentUserId);
 
         return (
           <OutlinerBlock