feat(i18n): Implement server-side internationalization support

- Added ServerI18nManager to handle translations and locale settings on the server.
- Integrated server-side translations into templates, reducing language flashing on initial load.
- Created API endpoints for setting and getting user language preferences.
- Enhanced client-side i18n handling to work seamlessly with server-rendered content.
- Updated various templates to utilize the new translation system.
- Added mixed i18n handler to coordinate server and client translations, improving user experience.
- Expanded translation files to include initialization messages for various components.

py/routes/stats_routes.py

@@ -9,6 +9,7 @@ from typing import Dict, List, Any
 
 from ..config import config
 from ..services.settings_manager import settings
+from ..services.server_i18n import server_i18n
 from ..services.service_registry import ServiceRegistry
 from ..utils.usage_stats import UsageStats
 
@@ -58,11 +59,32 @@ class StatsRoutes:
             
             is_initializing = lora_initializing or checkpoint_initializing or embedding_initializing
 
+            # 获取用户语言设置
+            user_language = settings.get('language', 'en')
+            
+            # 设置服务端i18n语言
+            server_i18n.set_locale(user_language)
+            
+            # 为模板环境添加i18n过滤器
+            if not hasattr(self.template_env, '_i18n_filter_added'):
+                self.template_env.filters['t'] = server_i18n.create_template_filter()
+                self.template_env._i18n_filter_added = True
+
             template = self.template_env.get_template('statistics.html')
             rendered = template.render(
                 is_initializing=is_initializing,
                 settings=settings,
-                request=request
+                request=request,
+                user_language=user_language,
+                # 添加服务端翻译函数
+                t=server_i18n.get_translation,
+                server_i18n=server_i18n,
+                # 添加一些常用的翻译到上下文
+                common_translations={
+                    'loading': server_i18n.get_translation('common.status.loading'),
+                    'error': server_i18n.get_translation('common.status.error'),
+                    'refresh': server_i18n.get_translation('common.actions.refresh'),
+                }
             )
             
             return web.Response(