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)

scripts/prepare-build-assets.mjs

@@ -11,6 +11,8 @@ const settingsSourceDir = path.join(repoRoot, 'src', 'settings');
 const settingsOutputDir = path.join(repoRoot, 'dist', 'settings');
 const syncUiSourceDir = path.join(repoRoot, 'src', 'syncui');
 const syncUiOutputDir = path.join(repoRoot, 'dist', 'syncui');
+const animeUiSourceDir = path.join(repoRoot, 'src', 'animeui');
+const animeUiOutputDir = path.join(repoRoot, 'dist', 'animeui');
 const scriptsOutputDir = path.join(repoRoot, 'dist', 'scripts');
 const macosHelperSourcePath = path.join(scriptDir, 'get-mpv-window-macos.swift');
 const macosHelperBinaryPath = path.join(scriptsOutputDir, 'get-mpv-window-macos');
@@ -47,6 +49,10 @@ function copySyncUiAssets() {
   copyAssets(syncUiSourceDir, syncUiOutputDir, 'syncui');
 }
 
+function copyAnimeUiAssets() {
+  copyAssets(animeUiSourceDir, animeUiOutputDir, 'animeui');
+}
+
 function fallbackToMacosSource() {
   copyFile(macosHelperSourcePath, macosHelperSourceCopyPath);
   process.stdout.write(`Staged macOS helper source fallback: ${macosHelperSourceCopyPath}\n`);
@@ -90,6 +96,7 @@ function main() {
   copyRendererAssets();
   copySettingsAssets();
   copySyncUiAssets();
+  copyAnimeUiAssets();
   buildMacosHelper();
 }