Centralize retained widget node destruction

docs/modernization/debt.md

@@ -584,6 +584,10 @@ agent or engineer to remove them without reconstructing context from chat.
   import/discard prompts and brush-package export completion now route retained
   dialog closing through `src/legacy_ui_overlay_services.*` instead of direct
   `destroy()` calls from service adapters.
+- 2026-06-12: DEBT-0063 was narrowed again. Flood-fill tool teardown and
+  checkbox icon removal now route retained node destruction through
+  `src/legacy_ui_overlay_services.*`. The underlying `Node` tree still exposes
+  raw child pointers and public destroy state.
 - 2026-06-05: DEBT-0011 was narrowed. The Windows app package smoke target now
   passes the configure-time CMake executable into `package-smoke.ps1`, so VS
   2026 generator validation does not depend on an older `cmake` on PATH, and