Fix #128012: disabling "Load UI" makes nodes unselectable

Resolve regression in [0] which caused the tool not to refresh
when loading a file without it's UI.

[0]: 83fe5712ab

source/blender/blenkernel/BKE_screen.hh

@@ -692,6 +692,12 @@ ScrArea *BKE_screen_find_area_xy(const bScreen *screen, int spacetype, const int
 
 void BKE_screen_gizmo_tag_refresh(bScreen *screen);
 
+/**
+ * Refresh any screen data that should be set on file-load
+ * with "Load UI" disabled.
+ */
+void BKE_screen_runtime_refresh_for_blendfile(bScreen *screen);
+
 void BKE_screen_view3d_sync(View3D *v3d, Scene *scene);
 void BKE_screen_view3d_scene_sync(bScreen *screen, Scene *scene);
 bool BKE_screen_is_fullscreen_area(const bScreen *screen) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();

source/blender/blenkernel/intern/blendfile.cc

@@ -956,6 +956,12 @@ static void setup_app_data(bContext *C,
         }
       }
     }
+
+    if (mode != LOAD_UI) {
+      LISTBASE_FOREACH (bScreen *, screen, &bfd->main->screens) {
+        BKE_screen_runtime_refresh_for_blendfile(screen);
+      }
+    }
   }
 
   /* Logic for 'track_undo_scene' is to keep using the scene which the active screen has, as long

source/blender/blenkernel/intern/screen.cc

@@ -481,6 +481,14 @@ void BKE_screen_gizmo_tag_refresh(bScreen *screen)
   }
 }
 
+void BKE_screen_runtime_refresh_for_blendfile(bScreen *screen)
+{
+  LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
+    area->runtime.tool = nullptr;
+    area->runtime.is_tool_set = false;
+  }
+}
+
 /**
  * Avoid bad-level calls to #WM_gizmomap_delete.
  */