feat(anime): add anime browser powered by Aniyomi extensions

- Add `subminer anime` / `--anime` and a tray entry to open a browser that searches installed Aniyomi extension sources, shows cover art and episodes, and plays into mpv with overlay/mining attached
- Add an Extensions tab to add repos and install/update/remove sources, and per-source settings for sources needing config
- Support searching all sources at once with streaming, per-source results and status
- Prefer Japanese audio/subtitle tracks from the source and keep the primary subtitle slot reserved for Japanese
- Fix window/tray/Dock handling so the browser and mpv can be switched between without quitting the app or losing the Dock icon
- Add anime.repos, anime.extensionsDir, anime.preferredQuality config keys (no bundled repos or discovery)

src/cli/help.ts

@@ -81,6 +81,7 @@ ${B}Jellyfin${R}
 
 ${B}Stats sync${R}
   --sync-window                  Open the stats sync window
+  --anime                        Open the anime browser
   --sync-cli sync ${D}[host] [opts]${R}   Headless stats sync ${D}(same commands as "subminer sync";${R}
                                  ${D}run SubMiner --sync-cli --help for details)${R}