Extract the shared request startup, completion, and cleanup flow so OpenAI and Anthropic routes keep the same wire behavior with less duplicated orchestration.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Keep the current tool-call bridge contract stable while extracting shared
execution setup and tightening Anthropic forwarding regressions.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>