feat: add subtitle search functionality and download feature

- Added subtitle search results support in zh-TW locale.
- Enhanced resource page to handle subtitle search results, including new computed properties and methods for managing subtitle data.
- Introduced SubtitleCard and SubtitleItem components for displaying subtitle information.
- Created AddSubtitleDownloadDialog for managing subtitle downloads with directory selection and media ID options.
- Implemented subtitle download caching mechanism to track downloaded subtitles.

src/utils/subtitleDownloadCache.ts

@@ -0,0 +1,13 @@
+import { reactive } from 'vue'
+
+const downloadedSubtitleMap = reactive<Record<string, boolean>>({})
+
+export function markSubtitleDownloaded(url?: string | null) {
+  if (!url) {
+    return
+  }
+
+  downloadedSubtitleMap[url] = true
+}
+
+export { downloadedSubtitleMap }