* test: initial commit enforcing testing on all anthropic pass through functions
prevents future regressions
* test(test_unit_test_anthropic_pass_through.py): add unit test for '_get_user_from_metadata' function
* test(test_unit_test_anthropic_passthrough.py): add unit test for handle_logging_anthropic_collected_chunks
* test(test_unit_test_anthropic_pass_through): add coverage for all anthropic pass through functions
* feat(pass_through_endpoints.py): fix anthropic end user cost tracking
* fix(anthropic/chat/transformation.py): use returned provider model for anthropic
handles anthropic `-latest` tag in request body throwing cost calculation errors
ensures we can be accurate in our model cost tracking
* feat(model_prices_and_context_window.json): add gemini-2.0-flash-thinking-exp pricing
* test: update test to use assumption that user_api_key_dict can get anthropic user id
* test: fix test
* fix: fix test
* fix(anthropic_pass_through.py): uncomment previous anthropic end-user cost tracking code block
can't guarantee user api key dict always has end user id - too many code paths
* fix(user_api_key_auth.py): this allows end user id from request body to always be read and set in auth object
* fix(auth_check.py): fix linting error
* test: fix auth check
* fix(auth_utils.py): fix get end user id to handle metadata = None
* run pass through logging async
* fix use thread_pool_executor for pass through logging
* test_pass_through_request_logging_failure_with_stream
* fix anthropic pt logging test
* test_pass_through_request_logging_failure
* allow passing _litellm_metadata in pass through endpoints
* fix _create_anthropic_response_logging_payload
* include litellm_call_id in logging
* add e2e testing for anthropic spend logs
* add testing for spend logs payload
* add example with anthropic python SDK
* use 1 file for AnthropicPassthroughLoggingHandler
* add support for anthropic streaming usage tracking
* ci/cd run again
* fix - add real streaming for anthropic pass through
* remove unused function stream_response
* working anthropic streaming logging
* fix code quality
* fix use 1 file for vertex success handler
* use helper for _handle_logging_vertex_collected_chunks
* enforce vertex streaming to use sse for streaming
* test test_basic_vertex_ai_pass_through_streaming_with_spendlog
* fix type hints
* add comment
* fix linting
* add pass through logging unit testing
