- Add default `f` fullscreen overlay binding and switch default AniSkip skip key to `Tab`
- Make character-dictionary auto-sync non-blocking at startup with tokenization gating for Yomitan mutations
- Add ordered startup OSD progress (checking/generating/updating/importing), refresh current subtitle on sync completion, and extend regression tests
- move JLPT/frequency dictionary init off sync fs APIs and add cooperative yielding during entry processing
- decouple first tokenization from full warmup by gating only on Yomitan readiness while MeCab/dictionary warmups continue in parallel
- update mpv pause-until-ready OSD copy to tokenization-focused wording and refresh gate regression assertions