Fix custom pricing - separate provider info from model info (#7990)

* fix(utils.py): initial commit fixing custom cost tracking

refactors out provider specific model info from `get_model_info` - this was causing custom costs to be registered incorrectly

* fix(utils.py): cleanup `_supports_factory` to check provider info, if model info is None

some providers support features like vision across all models

* fix(utils.py): refactor to use _supports_factory

* test: update testing

* fix: fix linting errors

* test: fix testing

litellm/llms/base_llm/base_utils.py

@@ -5,17 +5,15 @@ from typing import List, Optional, Type, Union
 from openai.lib import _parsing, _pydantic
 from pydantic import BaseModel
 
-from litellm.types.utils import ModelInfoBase
+from litellm.types.utils import ProviderSpecificModelInfo
 
 
 class BaseLLMModelInfo(ABC):
-    @abstractmethod
-    def get_model_info(
+    def get_provider_info(
         self,
         model: str,
-        existing_model_info: Optional[ModelInfoBase] = None,
-    ) -> Optional[ModelInfoBase]:
-        pass
+    ) -> Optional[ProviderSpecificModelInfo]:
+        return None
 
     @abstractmethod
     def get_models(self) -> List[str]: