fix(startup): --tray launch no longer flashes the window

With "Start with Windows" the window sat on screen for a second or two before
dropping to the tray. The hide was deferred with ForceQueue, which only runs
once the message loop is free — i.e. after the DB open, the HTTP server start
and the WebView2 init, all of which happen first.

Set Visible := False at the very top of FormCreate instead, before any of that
work, so there is nothing to show in the first place. The deferred
MinimizeToTray stays: it still adds the tray icon and drops the taskbar entry,
and doubles as the safety net if FMX shows the main form regardless — worst
case the behaviour is exactly what it is today.

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

delphi-backend/UMainForm.pas

@@ -206,6 +206,16 @@ procedure WinStateEventProc(hWinEventHook: THandle; AEvent: DWORD; AWnd: HWND;
 
 procedure TMainForm.FormCreate(Sender: TObject);
 begin
+  // --tray (the "Start with Windows" registry entry): never let the window
+  // become visible at all. Hiding it later — even via ForceQueue — only runs
+  // once the message loop is free, i.e. AFTER the DB open, the HTTP server
+  // start and the WebView2 init have finished, so the window sat on screen
+  // for a second or two during the Windows logon. Setting Visible here, before
+  // any of that, means there is nothing to flash. MinimizeToTray still runs
+  // below to add the tray icon and drop the taskbar entry.
+  if FindCmdLineSwitch('tray', True) then
+    Visible := False;
+
   // The .fmx ships WindowState = wsMaximized, so that is the starting intent.
   // Wired here (not in the .fmx) to keep the designer file untouched.
   FWantMaximized := (WindowState = TWindowState.wsMaximized);
@@ -300,8 +310,9 @@ begin
 
   // CLI flag --tray (set by the "Start with Windows" registry entry):
   // launch directly into the tray instead of popping a window during
-  // the Windows login. Defer to ForceQueue so the form has finished its
+  // the Windows login. The window was already made invisible at the top of
-  // initial Show before we hide it — minimises the visible flash.
+  // FormCreate; this adds the tray icon and drops the taskbar entry. Still
+  // deferred: it is also the safety net if FMX shows the main form anyway.
   if FindCmdLineSwitch('tray', True) then
   begin
     // Suppress the first-time tray balloon for autostart launches —