fix(vignette): Tamaños 16:9 para video + sin botón cerrar

- Agregados tamaños video: 1280x720, 960x540, 854x480, 800x450, 640x360, 560x315
- Eliminado botón de cerrar (usuario cierra haciendo clic fuera)
- Default cambiado a 960x540 (qHD)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Admin/AdsensePlacement/Infrastructure/Ui/AdsensePlacementFormBuilder.php

@@ -644,14 +644,15 @@ final class AdsensePlacementFormBuilder
             (string)$size,
             [
                 'auto' => 'Auto (recomendado)',
+                'responsive' => 'Responsive (fluid)',
+                '1280x720' => '1280x720 (HD 720p)',
+                '960x540' => '960x540 (qHD)',
+                '854x480' => '854x480 (480p)',
+                '800x450' => '800x450 (16:9)',
+                '640x360' => '640x360 (360p)',
+                '560x315' => '560x315 (YouTube)',
                 '300x250' => '300x250 (Rectangle)',
                 '336x280' => '336x280 (Large Rectangle)',
-                '728x90' => '728x90 (Leaderboard)',
-                '970x250' => '970x250 (Billboard)',
-                '970x90' => '970x90 (Large Leaderboard)',
-                '468x60' => '468x60 (Banner)',
-                '320x100' => '320x100 (Large Mobile)',
-                'responsive' => 'Responsive (fluid)',
             ]
         );
         $html .= '    </div>';