feat(webui): add search provider settings panel

- Add config-search-provider.vue component for managing search sources
- Support CRUD operations for custom search providers
- Default providers (mikan, nyaa, dmhy) cannot be deleted
- URL template validation ensures %s placeholder is present
- Add backend API endpoints GET/PUT /search/provider/config
- Add i18n translations for zh-CN and en

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/src/module/api/search.py

@@ -1,6 +1,7 @@
 from fastapi import APIRouter, Depends, Query
 from sse_starlette.sse import EventSourceResponse
 
+from module.conf.search_provider import get_provider, save_provider
 from module.models import Bangumi
 from module.searcher import SEARCH_CONFIG, SearchTorrent
 from module.security.api import UNAUTHORIZED, get_current_user
@@ -32,3 +33,24 @@ async def search_torrents(site: str = "mikan", keywords: str = Query(None)):
 )
 async def search_provider():
     return list(SEARCH_CONFIG.keys())
+
+
+@router.get(
+    "/provider/config",
+    response_model=dict[str, str],
+    dependencies=[Depends(get_current_user)],
+)
+async def get_search_provider_config():
+    """Get all search providers with their URL templates."""
+    return get_provider()
+
+
+@router.put(
+    "/provider/config",
+    response_model=dict[str, str],
+    dependencies=[Depends(get_current_user)],
+)
+async def update_search_provider_config(providers: dict[str, str]):
+    """Update search providers configuration."""
+    save_provider(providers)
+    return get_provider()