fix(setup): resolve series key from search link field

- Fix _resolve_key_via_search to use 'title' instead of 'name'
- Extract key from 'link' field URL (e.g., /anime/stream/naruto -> naruto)
- Skip folders with unresolved keys instead of crashing with 'Series key cannot be empty'
- Update tests to use correct field names (title/link)

src/server/services/setup_service.py

@@ -93,9 +93,11 @@ class SetupService:
             results = await series_app.search(title)
             
             if len(results) == 1:
-                result_name = results[0].get('name', '').lower()
+                result_name = results[0].get('title', '').lower()
                 if result_name == title.lower():
-                    return results[0].get('key', '')
+                    link = results[0].get('link', '')
+                    if link and '/anime/stream/' in link:
+                        return link.split('/anime/stream/')[-1].split('/')[0]
         except Exception as e:
             logger.warning(
                 "Provider search failed for folder",
@@ -236,6 +238,13 @@ class SetupService:
                     # Resolve key via provider search
                     resolved_key = await cls._resolve_key_via_search(title)
                     
+                    if not resolved_key:
+                        logger.warning(
+                            "Could not resolve series key for folder, skipping: %s",
+                            folder_name
+                        )
+                        continue
+                    
                     # Check filesystem properties
                     props = cls._get_series_properties(folder)