fix(window): use foreground ownership to tell a user resize from a restore

The log settled the previous attempt: WPF_RESTORETOMAXIMIZED (flags=2) is set
for ANY maximised window, not just one on its way back from minimised, and
showCmd is already 1/3 by the time the resize fires. Testing those classified
the user's own Maximize click as a restore, so the intent was never recorded
(want stayed False) and nothing could be re-applied afterwards.

Windows exposes no restore marker here. What does separate the two: a user
gesture happens while the window OWNS THE FOREGROUND; FMX's re-layout during a
restore (and during the startup burst) runs before it does. Resizes that
arrive without foreground ownership are no longer recorded as intent, and
re-apply a maximised state the user had left.

Placement is still read, for the log only.

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

delphi-backend/UMainForm.pas

@@ -1520,24 +1520,27 @@ begin
   if LHwnd = 0 then Exit;
   if IsIconic(LHwnd) then Exit;          // nothing to learn while minimised
 
-  // OnActivate turned out to be useless as a "the window came back" signal —
+  // Windows offers no usable "this resize is a restore" signal: the log showed
-  // it also fires on plain focus churn with the WebView2 child, and even right
+  // WPF_RESTORETOMAXIMIZED (flags=2) is set for ANY maximised window, and
-  // after the user clicks Maximize. Ask Windows instead: WPF_RESTORETOMAXIMIZED
+  // showCmd is already 1/3 by then — testing those classified the user's own
-  // means "this window is on its way back from minimised and belongs
+  // Maximize click as a restore and dropped the intent.
-  // maximised", which is exactly the resize we must not mistake for the user
+  //
-  // un-maximising.
+  // What does separate them: a user gesture happens while the window is the
-  FillChar(LPlace, SizeOf(LPlace), 0);
+  // FOREGROUND window. FMX's re-layout during a restore (and during startup)
+  // runs before the window owns the foreground.
+  LIsRestore := GetForegroundWindow <> LHwnd;
+  FillChar(LPlace, SizeOf(LPlace), 0);          // diagnostics only
   LPlace.length := SizeOf(LPlace);
-  LIsRestore := GetWindowPlacement(LHwnd, @LPlace) and
+  GetWindowPlacement(LHwnd, @LPlace);
-                (((LPlace.flags and WPF_RESTORETOMAXIMIZED) <> 0) or
+  LogLine(Format('[winstate] resize zoomed=%s showCmd=%d flags=%d fg=%s want=%s',
-                 (LPlace.showCmd = SW_SHOWMINIMIZED));
-  LogLine(Format('[winstate] resize zoomed=%s showCmd=%d flags=%d restore=%s want=%s',
     [BoolToStr(IsZoomed(LHwnd), True), LPlace.showCmd, LPlace.flags,
-     BoolToStr(LIsRestore, True), BoolToStr(FWantMaximized, True)]));
+     BoolToStr(not LIsRestore, True), BoolToStr(FWantMaximized, True)]));
 
   if LIsRestore then
   begin
-    // Re-apply after FMX has finished sizing; doing it inline loses the race.
+    // Not a user gesture — never record it as intent. If it dropped a window
+    // the user had left maximised, put it back (queued: inline loses the race
+    // against FMX's own sizing).
     if FWantMaximized and (not IsZoomed(LHwnd)) and (not FRestoring) then
     begin
       FRestoring := True;
@@ -1552,7 +1555,7 @@ begin
           ShowWindow(LH, SW_SHOWMAXIMIZED);
         end);
     end;
-    Exit;                                 // never record a restore as intent
+    Exit;
   end;
   if FRestoring then Exit;                // our own ShowWindow's resize
   FWantMaximized := IsZoomed(LHwnd);      // genuine user gesture