fix(quick-search): Esc closes only the modal; cancel returns focus to target

- The qsInput Esc handler didn't stopPropagation, so the SAME keystroke fell
  through to the document-level Esc handlers which, seeing the modal now
  closed, also closed (or discard-prompted) the dirty slideover behind it.
- autofill/cancel now hands the foreground back to the saved target HWND:
  Esc after a fill-mode hotkey returns the user to the window they came
  from instead of leaving our app focused. Locked-vault path still ends
  focused on us (cancelAutofill runs before focusApp).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

delphi-backend/UMainForm.pas

@@ -921,8 +921,13 @@ begin
   end
 
   // cancel: JS found no match or user dismissed the picker — nothing to type.
+  // Hand the foreground back to the window the hotkey came from (Esc in the
+  // quick-search means "never mind, return me to where I was"). We're the
+  // foreground process at that moment, so plain SetForegroundWindow works.
   else if ACmd = 'autofill/cancel' then
   begin
+    if FAutofillTargetHWND <> 0 then
+      SetForegroundWindow(FAutofillTargetHWND);
     FAutofillTargetHWND := 0;
     LogLine('Autofill cancelled (no match or dismissed)');
   end