feat: promote downloader queue, cache, and recovery pipeline

[Priveetee]

Summary

• add a production downloader pipeline with asynchronous jobs, Dragonfly queue backpressure, Garage artifact caching, and TypeType-Token integration for YouTube tokenized extraction
• expand job lifecycle support with persisted options, cancellation, deletion, startup recovery/requeue, and stronger option normalization/selector handling for audio, video, subtitles, sponsorblock, and wrapper URL inputs
• harden runtime behavior with Garage S3 compatibility fixes, non-simulated yt-dlp execution, SQL timestamp persistence, and new unit coverage for cache keys, URL resolution, options normalization, control flows, and recovery

Validation

• ./gradlew test
• ./gradlew build
• CI / Coverage / Docker workflows are green on dev