9.0.0: History highlighting via `visited-service` and new styles.

Added

• src/shared/services/visited-service.ts + interval.utils.ts.
• src/content/styles/visited.scss.

Changed

• Integrated visited tracking into Bandcamp page services and page-service-worker.
• config-model and config-service for highlight control.
• Brand assets (banner/logos) and manifest.

Full Changelog: 8.0.4...9.0.0