Support caching on reasoning content + other fixes (#8973)

* fix(factory.py): pass on anthropic thinking content from assistant call

* fix(factory.py): fix anthropic messages to handle thinking blocks

Fixes https://github.com/BerriAI/litellm/issues/8961

* fix(factory.py): fix bedrock handling for assistant content in messages

Fixes https://github.com/BerriAI/litellm/issues/8961

* feat(convert_dict_to_response.py): handle reasoning content + thinking blocks in chat completion block

ensures caching works for anthropic thinking block

* fix(convert_dict_to_response.py): pass all message params to delta block

ensures streaming delta also contains the reasoning content / thinking block

* test(test_prompt_factory.py): remove redundant test

anthropic now supports assistant as the first message

* fix(factory.py): fix linting errors

* fix: fix code qa

* test: remove falsy test

* fix(litellm_logging.py): fix str conversion

litellm/caching/caching_handler.py

@@ -247,7 +247,6 @@ class LLMCachingHandler:
                     pass
                 else:
                     call_type = original_function.__name__
-
                     cached_result = self._convert_cached_result_to_model_response(
                         cached_result=cached_result,
                         call_type=call_type,
@@ -725,6 +724,7 @@ class LLMCachingHandler:
         """
         Sync internal method to add the result to the cache
         """
+
         new_kwargs = kwargs.copy()
         new_kwargs.update(
             convert_args_to_kwargs(
@@ -738,6 +738,7 @@ class LLMCachingHandler:
         if self._should_store_result_in_cache(
             original_function=self.original_function, kwargs=new_kwargs
         ):
+
             litellm.cache.add_cache(result, **new_kwargs)
 
         return