fix: deleteWithUndo uses _reloadAfterAction() instead of manual tree manipulation

Replaced fragile _removeFromTree() + displayTree spread (which had Alpine
reactivity issues) with a clean _reloadAfterAction() call that reloads the
tree from the API. This is the same approach used by doDelete() and
doRename(), which work reliably. _reloadAfterAction also triggers the
sidebar refresh via window.appState.refreshSidebarTree().

app/templates/local_workspace.html

@@ -1209,23 +1209,16 @@ window._wsInitData = (function() {
       this.undoItemId = node.db_id || node.id;
       this.undoMessage = 'Deleted "' + (node.name || 'item') + '"';
       this.undoVisible = true;
-      // Soft-delete: actually delete after timeout
+      // Delete via API
       var r = await fetch('/api/local-workspace/items/' + this.undoItemId, { method:'DELETE' });
       if (!r.ok) { this.undoVisible = false; return; }
-      // Remove from tree immediately
-      this._removeFromTree(this.tree, this.undoItemId);
-      if (!this.searchQuery && !this.filterType && !this.sortBy) this.displayTree = [...this.tree];
-      else if (this.sortBy) this.doSort();
-      else this.doFilter();
-      // Auto-dismiss + permanent after 5s
+      // Reload from API for reliability (sidebar refresh handled by _reloadAfterAction)
+      this._reloadAfterAction();
+      // Auto-dismiss undo banner after 5s
       this.undoTimeout = setTimeout(function() {
         self.undoVisible = false;
         self.undoItemId = null;
       }, 5000);
-      // Directly refresh sidebar tree
-      if (window.appState && window.appState.refreshSidebarTree) {
-        window.appState.refreshSidebarTree();
-      }
     },
     undoDelete() {
       if (this.undoTimeout) clearTimeout(this.undoTimeout);