Fix: scaling window size difference

docs/RELEASE_TESTING.md

@@ -142,6 +142,9 @@ Bevy window-management verification workflow: `docs/BEVY_WINDOW_VERIFICATION.md`
  - at large scale values (>= 1.8), full sprite remains visible without clipping
 13. Verify packaged tauri frontend freshness:
 - confirm package run reflects latest `frontend/tauri-ui` changes (no stale embedded UI bundle)
+14. Verify packaged tauri overlay edge and scale consistency:
+- place overlay over dark background and confirm no white strip/background bleed on left edge
+- for same slider value, confirm main-window size is consistent across `default`/`ferris`/`demogorgon`
 
 ### Packaged Mode (Required Once Tauri Packaging Exists)
 

docs/TAURI_RUNTIME_TESTING.md

@@ -122,6 +122,9 @@ An issue touching Tauri runtime behaviors must satisfy all requirements before `
   API mismatch)
 - verify window resize uses consistent coordinate units (no accumulated drift over 20 scale changes)
 - no runtime command/type error from position updates (e.g. `set_position` expects integer coords)
+- at the same slider scale value, main window size is consistent across packs (`default`, `ferris`,
+  `demogorgon`) within 1px rounding tolerance
+- no white strip/background bleed is visible along any overlay window edge on dark desktop background
 
 ## Settings Window Checklist