builder doesn't de-select after building a tower

Assets/_Project/Scripts/Gameplay/TowerPlacementController.cs

@@ -58,6 +58,11 @@ namespace TD.Gameplay
         private TowerDefinition activeDef;
         private int activeTowerTypeId;
 
+        // Set true by a single-shot placement submit; processed at the top of the next
+        // Update so that BuilderInputController still sees IsPlacing=true on the same
+        // frame as the click and doesn't deselect the builder via its empty-space check.
+        private bool pendingCancel;
+
         // The cursor ghost GameObject: the tower prefab instantiated with transparent materials.
         // Null when placement mode is inactive.
         private GameObject ghostGO;
@@ -100,6 +105,13 @@ namespace TD.Gameplay
 
         private void Update()
         {
+            if (pendingCancel)
+            {
+                pendingCancel = false;
+                CancelPlacement();
+                return;
+            }
+
             if (activeDef == null) return;     // idle — nothing to do
 
             var mouse = Mouse.current;
@@ -375,8 +387,9 @@ namespace TD.Gameplay
                 return;
             }
 
-            // Single-shot: exit placement mode immediately.
-            CancelPlacement();
+            // Single-shot: defer the cancel to the next frame so BuilderInputController
+            // still sees IsPlacing=true this frame and doesn't deselect the builder.
+            pendingCancel = true;
         }
 
         // ----- Rejection feedback -----------------------------------------