Fix Windows overlay z-order on minimize/restore and improve hover stability

Use native synchronous z-order binding (koffi) instead of async PowerShell
for overlay positioning, eliminating the 200-500ms delay that left the overlay
behind mpv after restore. Hide the overlay immediately when mpv is minimized
so the full show/reveal/z-order flow triggers cleanly on restore.

Also adds hover suppression after visibility recovery and window resize to
prevent spurious auto-pause, Windows secondary subtitle titlebar fix, and
z-order sync burst retries on geometry changes.

scripts/get-mpv-window-windows.ps1

@@ -302,6 +302,7 @@ public static class SubMinerWindowsHelper {
 
     [IntPtr]$overlayWindow = [IntPtr]([int64]$OverlayWindowHandle)
     $targetWindow = [IntPtr]$bestMatch.HWnd
+    [void][SubMinerWindowsHelper]::SetWindowLongPtr($overlayWindow, $GWLP_HWNDPARENT, $targetWindow)
     $targetWindowExStyle = [SubMinerWindowsHelper]::GetWindowLong($targetWindow, $GWL_EXSTYLE)
     $targetWindowIsTopmost = ($targetWindowExStyle -band $WS_EX_TOPMOST) -ne 0