fix(ui/templates): defer deep-link reveal until TreeView restores sessionStorage

Both page.OnAfterRenderAsync(firstRender=true) and
TreeView.OnAfterRenderAsync(firstRender=true) ran concurrently:
- Page called RevealNode → added ancestor keys to _expandedKeys
- TreeView awaited treeviewStorage.load → replaced _expandedKeys with
  the persisted set (often empty if user collapsed before navigating)

Whichever JS interop completed second won. When TreeView won, the deep-link
reveal silently lost. Gate the reveal on firstRender==false so it runs
strictly after TreeView's restore is done.

src/ScadaLink.CentralUI/Components/Pages/Design/Templates.razor

@@ -177,10 +177,15 @@
         }
     }
 
+    private bool _revealApplied;
+
     protected override async Task OnAfterRenderAsync(bool firstRender)
     {
-        if (firstRender && TemplateIdParam > 0 && _tree != null)
+        // Wait until second render so TreeView has finished restoring its sessionStorage
+        // expansion state; otherwise that restore races with RevealNode and overwrites it.
+        if (!_revealApplied && !firstRender && TemplateIdParam > 0 && _tree != null)
         {
+            _revealApplied = true;
             await _tree.RevealNode($"t:{TemplateIdParam}", select: true);
         }
     }