fix(openrouter): add strict typing annotations to config and exception classes

litellm/exceptions.py

@@ -238,7 +238,7 @@ class OpenRouterRegionNotSupportedError(NotFoundError):
         max_retries: int | None = None,
         num_retries: int | None = None,
         region: str | None = None,
-    ):
+    ) -> None:
         self.region = region
         super().__init__(
             message=message,

litellm/llms/openrouter/chat/transformation.py

@@ -52,8 +52,8 @@ class OpenrouterConfig(OpenAIGPTConfig):
     def __init__(
         self,
         region: str | None = None,
-        **kwargs,
-    ):
+        **kwargs: object,
+    ) -> None:
         self.region = region
         super().__init__(**kwargs)