feat: download latest season only + fix lpayer CDN + HLS support

- Watchlist 'Suivre' now downloads only the latest season instead of all episodes
- Fix lpayer CDN 403 errors by adding proper Referer header for IP ranges
- Add HLS/m3u8 stream download support using ffmpeg
- Improve episode filename format: 'Anime - SX - Episode XX.mp4'
- Add CDN detection for lpayer IPs (185.237.x.x, 203.188.x.x, /mik/ path)

main.py

@@ -2094,9 +2094,12 @@ async def check_watchlist_item(
 @app.post("/api/watchlist/{item_id}/download-all", tags=["Watchlist"])
 async def download_all_episodes(
     item_id: str,
+    background_tasks: BackgroundTasks,
     current_user: User = Depends(get_current_user_from_token)
 ):
-    """Download ALL episodes for a watchlist item (used when first following an anime)"""
+    """Download the LATEST SEASON episodes for a watchlist item (used when first following an anime)"""
+    from app.downloaders import get_downloader
+
     try:
         item = watchlist_manager.get_by_id(item_id)
         if not item:
@@ -2105,18 +2108,64 @@ async def download_all_episodes(
         if item.user_id != current_user.id:
             raise HTTPException(status_code=403, detail="Access denied")
 
-        # Temporarily set last_episode_downloaded to 0 to trigger download of ALL episodes
-        watchlist_manager.update(item_id, {"last_episode_downloaded": 0})
+        downloader = get_downloader(item.anime_url)
+        latest_season_url = item.anime_url  # Default to current URL
 
-        result = await episode_checker.manual_check(item_id)
+        # Try to get the latest season if provider supports it
+        if hasattr(downloader, 'get_seasons'):
+            try:
+                seasons = await downloader.get_seasons(item.anime_url)
+                if seasons and len(seasons) > 0:
+                    # Get the last season (most recent)
+                    latest_season = seasons[-1]
+                    latest_season_url = latest_season.get('url', item.anime_url)
+                    logger.info(f"Found {len(seasons)} seasons, using latest: {latest_season.get('title', 'unknown')}")
+            except Exception as e:
+                logger.warning(f"Could not fetch seasons, using default URL: {e}")
 
-        # Note: download_new_episodes already updates last_episode_downloaded via update_check_time
-        # So we don't restore the original value - the new value reflects what was actually downloaded
+        # Get episodes from the latest season
+        episodes = await downloader.get_episodes(latest_season_url, item.lang)
+
+        if not episodes:
+            return {
+                "status": "warning",
+                "message": f"No episodes found for {item.anime_title}",
+                "result": {"new_episodes_found": 0, "episodes_downloaded": []}
+            }
+
+        # Create download tasks for all episodes of the latest season
+        task_ids = []
+        
+        # Extract season number from URL for filename
+        import re
+        season_match = re.search(r'saison(\d+)', latest_season_url, re.IGNORECASE)
+        season_num = season_match.group(1) if season_match else "1"
+        
+        # Clean anime title for filename
+        anime_title_clean = item.anime_title.replace('/', '-').replace('\\', '-').strip()
+        
+        for episode in episodes:
+            # Build a nice filename: "Anime Title - S1 - Episode 01.mp4"
+            ep_num = episode.get('episode', '01')
+            filename = f"{anime_title_clean} - S{season_num} - Episode {ep_num}.mp4"
+            
+            request = DownloadRequest(url=episode['url'], filename=filename)
+            task = download_manager.create_task(request)
+            task_ids.append(task.id)
+            background_tasks.add_task(download_manager.start_download, task.id)
+
+        # Update watchlist with total episodes count
+        watchlist_manager.update(item_id, {
+            "last_episode_downloaded": len(episodes),
+            "total_episodes": len(episodes)
+        })
 
         return {
             "status": "success",
-            "message": f"Downloading all episodes for {item.anime_title}",
-            "result": result
+            "message": f"Downloading {len(task_ids)} episodes from latest season for {item.anime_title}",
+            "task_ids": task_ids,
+            "total_episodes": len(episodes),
+            "season_url": latest_season_url
         }
     except HTTPException:
         raise