fix(window): a maximised window comes back maximised after Show desktop

Win+D / Show desktop minimises the window without any tray transition, so the
restore took the non-tray branch. FMainForm.Show runs first there and
re-applies FMX's own WindowState (normal), discarding the
WPF_RESTORETOMAXIMIZED flag Windows had recorded — the app returned in normal
size.

Read the placement flag BEFORE showing, and re-apply SW_SHOWMAXIMIZED when it
was set. The tray path is untouched: it already replays its own captured
placement.

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

delphi-backend/Source/PM.Bridge.pas

@@ -693,7 +693,8 @@ end;
 procedure TPMBridge.RestoreFromTray;
 var
   LFormHwnd, LAppHwnd: HWND;
-  LWasTrayHidden: Boolean;
+  LWasTrayHidden, LRestoreMax: Boolean;
+  LPlace: TWindowPlacement;
 begin
   // Tray icon stays in the tray — we only show the window again.
   LFormHwnd := MainFormHWND(FMainForm);
@@ -713,6 +714,19 @@ begin
   // MinimizeToTray) vs merely taskbar-minimised (Visible but iconic).
   LWasTrayHidden := not FMainForm.Visible;
 
+  // Windows remembers "this minimised window was maximised" in the placement
+  // flags, but FMainForm.Show below re-applies FMX's own WindowState (normal)
+  // and loses it — hence a maximised window coming back normal after Win+D /
+  // Show desktop. Read the flag BEFORE showing so we can re-apply it.
+  LRestoreMax := False;
+  if not LWasTrayHidden then
+  begin
+    FillChar(LPlace, SizeOf(LPlace), 0);
+    LPlace.length := SizeOf(LPlace);
+    LRestoreMax := GetWindowPlacement(LFormHwnd, @LPlace) and
+                   ((LPlace.flags and WPF_RESTORETOMAXIMIZED) <> 0);
+  end;
+
   // Reverse order: show the app proxy first so the taskbar entry comes back,
   // then show and foreground the form.
   if LAppHwnd <> 0 then
@@ -747,6 +761,11 @@ begin
     end;
     SetWindowPlacement(LFormHwnd, @FSavedPlacement);
   end
+  else if LRestoreMax then
+    // Was maximised before Windows minimised it (Win+D, taskbar, Show
+    // desktop): come back maximised. SW_RESTORE alone would land on the
+    // pre-maximise "normal" geometry.
+    ShowWindow(LFormHwnd, SW_SHOWMAXIMIZED)
   else
   begin
     ShowWindow(LFormHwnd, SW_SHOW);