feat: Ctrl+Shift+Q quick-search-fill + Edge browser directive

Ctrl+Shift+Q quick-search + autofill
- New global hotkey: capture the foreground HWND, restore the window
  if hidden, pop the quick-search modal in "fill mode". On pick, the
  password is SendInput'd into the saved HWND — no clipboard touch.
- hide_after flag added to cmd://autofill/execute: when set (tray-mode
  hotkey), Delphi MinimizeToTray's *after* SendInput completes. Hiding
  before SendInput would trip Win10/11 anti-focus-stealing rules and
  block focus handoff to the target.
- Quick-search modal hint text adapts to fill vs copy mode.
- Esc / close in fill mode sends cmd://autofill/cancel so a stale
  HWND doesn't get reused by an unrelated Ctrl+Shift+L later.

Compile-time browser engine switch
- {.$DEFINE USE_EDGE_BROWSER} in UMainForm.pas selects between
  TTMSFNCWebBrowser (default, cross-platform abstraction) and
  TTMSFNCEdgeWebBrowser (Windows-only WebView2 wrapper). Both
  inherit from TTMSFNCCustomWebBrowser so the bridge cmd:// glue is
  unchanged; the field type is a conditional alias TWebBrowserClass.
- WebBrowser is created dynamically in FormCreate so neither variant
  needs a second .fmx. Events are wired BEFORE Parent assignment so
  OnInitialized doesn't race the WebView2 async init on fast/pre-warmed
  Edge installs (was silently missing the disable-context-menu /
  disable-accelerator-keys calls).
- Native context menu disabled by assigning an empty PopupMenu1 (works
  for both backends, unlike OnGetContextMenu which is publish-gated
  via {$IFNDEF FNCLIB} on TTMSFNCWebBrowser).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

delphi-backend/UMainForm.fmx

@@ -123,12 +123,8 @@ object MainForm: TMainForm
     Size.Height = 6.000000000000000000
     Size.PlatformDefault = False
   end
-  object WebBrowser: TTMSFNCWebBrowser
-    Align = Client
-    Size.Width = 1100.000000000000000000
-    Size.Height = 502.000000000000000000
-    Size.PlatformDefault = False
-    TabOrder = 3
-    DesigntimeEnabled = False
+  object PopupMenu1: TPopupMenu
+    Left = 424
+    Top = 240
   end
 end