prepare_metadata
* test_langfuse_logging_completion_with_langfuse_metadata * fix litellm - remove prepare metadata * test_langfuse_logging_with_non_serializable_metadata * detailed e2e langfuse metadata tests * clean up langfuse logging * fix langfuse * remove unused imports * fix code qa checks * fix _prepare_metadata
* move langfuse tests * fix test * fix completion.json * working test * test completion with tags * langfuse testing fixes * faster logging testing * pytest-xdist in testing * fix langfuse testing flow * fix testing flow * fix config for logging tests * fix langfuse completion with tags stream * fix _verify_langfuse_call