feat: Add anime metadata extraction and fix episode selection bug

Features:
- Added rich metadata extraction for all anime providers (Anime-Sama, Neko-Sama, Anime-Ultime, Vostfree)
- New AnimeMetadata model with synopsis, genres, rating, release year, studio, poster/banner images, episode count, and status
- New /api/anime/metadata endpoint for fetching metadata of specific anime
- Enhanced /api/anime/search endpoint with optional include_metadata parameter
- Updated web interface with metadata display (expandable synopsis, genres, rating, year)
- Added metadata toggle checkbox in search UI (disabled by default for performance)

Bug Fixes:
- Fixed episode selection bug where select would reset to default after any change
- Removed onchange event from select element that was causing unwanted reloads
- Fixed download button disappearing after episode download
- Episodes can now be downloaded multiple times without page refresh

Enhancements:
- Metadata displayed with icons (📅 year, ⭐ rating, 🏷️ genres, 📺 episodes, 📡 status)
- Expandable synopsis section for detailed descriptions
- Better visual organization of anime information
- Maintains backward compatibility (metadata is optional)

Generated with [Claude Code](https://claude.ai/code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

main.py

@@ -42,7 +42,7 @@ async def root():
     return {
         "message": "Ohm Stream Downloader API",
         "status": "running",
-        "version": "2.0",
+        "version": "2.1",
         "endpoints": {
             "POST /api/download": "Start a new download",
             "GET /api/downloads": "List all downloads",
@@ -51,6 +51,10 @@ async def root():
             "POST /api/download/{task_id}/resume": "Resume a download",
             "DELETE /api/download/{task_id}": "Cancel a download",
             "GET /api/providers": "List all supported providers",
+            "GET /api/anime/search": "Search anime across all providers",
+            "GET /api/anime/metadata": "Get detailed anime metadata (synopsis, genres, rating, etc.)",
+            "GET /api/anime/episodes": "Get episode list for an anime",
+            "POST /api/anime/download-season": "Download all episodes of a season",
             "GET /web": "Web interface"
         }
     }
@@ -156,14 +160,21 @@ async def download_file(task_id: str):
 
 # Unified Anime Search endpoints
 @app.get("/api/anime/search")
-async def search_anime_unified(q: str, lang: str = "vostfr"):
-    """Search across all anime providers"""
+async def search_anime_unified(q: str, lang: str = "vostfr", include_metadata: bool = False):
+    """
+    Search across all anime providers
+
+    Args:
+        q: Search query
+        lang: Language preference (vostfr, vf)
+        include_metadata: Whether to fetch full metadata (slower but more detailed)
+    """
     import time
     import asyncio
     from app.providers import get_anime_providers
     from app.downloaders import AnimeSamaDownloader, AnimeUltimeDownloader, NekoSamaDownloader, VostfreeDownloader
 
-    print(f"\n[SEARCH] Starting search for '{q}' in {lang}")
+    print(f"\n[SEARCH] Starting search for '{q}' in {lang} (metadata={include_metadata})")
     start_time = time.time()
 
     results = {}
@@ -184,7 +195,7 @@ async def search_anime_unified(q: str, lang: str = "vostfr"):
         if provider_id in downloaders:
             downloader = downloaders[provider_id]
             print(f"[SEARCH] Queueing search on {provider_id}...")
-            search_tasks.append(downloader.search_anime(q, lang))
+            search_tasks.append(downloader.search_anime(q, lang, include_metadata=include_metadata))
             provider_ids.append(provider_id)
 
     # Wait for all searches to complete with a timeout per provider
@@ -207,10 +218,41 @@ async def search_anime_unified(q: str, lang: str = "vostfr"):
     return {
         "query": q,
         "lang": lang,
+        "include_metadata": include_metadata,
         "results": results
     }
 
 
+@app.get("/api/anime/metadata")
+async def get_anime_metadata(url: str):
+    """
+    Get detailed metadata for a specific anime
+
+    Args:
+        url: The anime page URL
+    """
+    from app.downloaders import get_downloader
+
+    try:
+        downloader = get_downloader(url)
+
+        # Check if the downloader has metadata support
+        if hasattr(downloader, 'get_anime_metadata'):
+            metadata = await downloader.get_anime_metadata(url)
+            return {
+                "url": url,
+                "metadata": metadata
+            }
+        else:
+            raise HTTPException(
+                status_code=400,
+                detail=f"Downloader for {url} does not support metadata extraction"
+            )
+
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=str(e))
+
+
 @app.get("/api/anime/episodes")
 async def get_anime_episodes(url: str, lang: str = "vostfr"):
     """Get list of episodes for an anime"""