fix(patreon): declare aiohttp/yarl deps and use public yarl.URL import

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/services/patreon_resolver.py

@@ -12,6 +12,7 @@ import os
 from typing import Optional
 
 import aiohttp
+from yarl import URL
 
 logger = logging.getLogger(__name__)
 
@@ -42,7 +43,7 @@ def _load_cookie_jar(cookies_path: Optional[str]) -> Optional[aiohttp.CookieJar]
     for cookie in moz:
         jar.update_cookies(
             {cookie.name: cookie.value},
-            response_url=aiohttp.helpers.URL(
+            response_url=URL(
                 f"https://{cookie.domain.lstrip('.')}/"
             ),
         )