* 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
