fix: simulator video quality — hide banners via CSS injection, reduce reloads

- Inject CSS via addInitScript to hide Figma cookie banner and hardware
  acceleration warning before DOM renders (no more bottom banners in video)
- Auto-click dismiss buttons (allow cookies, got it) after 2s
- Hide any bottom-anchored div matching cookie/hardware/performance text
- Remove runtime dismissBanners() — all handled at context level now

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: oxxo