fix：优化单例模式和类引用

app/chain/tmdb.py

@@ -3,13 +3,11 @@ from typing import Optional, List
 
 from app import schemas
 from app.chain import ChainBase
-from app.core.cache import cached
 from app.core.context import MediaInfo
 from app.schemas import MediaType
-from app.utils.singleton import Singleton
 
 
-class TmdbChain(ChainBase, metaclass=Singleton):
+class TmdbChain(ChainBase):
     """
     TheMovieDB处理链，单例运行
     """
@@ -145,7 +143,6 @@ class TmdbChain(ChainBase, metaclass=Singleton):
         """
         return self.run_module("tmdb_person_credits", person_id=person_id, page=page)
 
-    @cached(maxsize=1, ttl=3600)
     def get_random_wallpager(self) -> Optional[str]:
         """
         获取随机壁纸，缓存1个小时
@@ -159,7 +156,6 @@ class TmdbChain(ChainBase, metaclass=Singleton):
                     return info.backdrop_path
         return None
 
-    @cached(maxsize=1, ttl=3600)
     def get_trending_wallpapers(self, num: Optional[int] = 10) -> List[str]:
         """
         获取所有流行壁纸