Gradio API migration, training pipeline, news page, and UI improvements

- Migrate backend from REST API to Gradio @gradio/client for generation
- Fix Gradio parameter alignment (positions 36-49) for reference/cover audio
- Add LoRA training pipeline with dataset upload, preprocessing, and export
- Add News page with dismiss/restore and GitHub star button
- Add localization info icon in Settings language section
- Fix upload audio URL prefix, add missing MIME types
- Add training API routes and Python preprocess script
- Update i18n with news keys for all languages

i18n/translations.ts

@@ -7,7 +7,8 @@ export const translations = {
     library: 'Library',
     search: 'Search',
     training: 'Training',
-    
+    news: 'News',
+
     // Theme
     lightMode: 'Light Mode',
     darkMode: 'Dark Mode',
@@ -601,7 +602,8 @@ export const translations = {
     library: '音乐库',
     search: '搜索',
     training: '训练',
-    
+    news: '新闻',
+
     // Theme
     lightMode: '浅色模式',
     darkMode: '深色模式',
@@ -1195,7 +1197,8 @@ export const translations = {
     library: 'ライブラリ',
     search: '検索',
     training: 'トレーニング',
-    
+    news: 'ニュース',
+
     // Theme
     lightMode: 'ライトモード',
     darkMode: 'ダークモード',
@@ -1789,7 +1792,8 @@ export const translations = {
     library: '라이브러리',
     search: '검색',
     training: '훈련',
-    
+    news: '뉴스',
+
     // Theme
     lightMode: '라이트 모드',
     darkMode: '다크 모드',