Claude Session URL appended to commit messages and PR descriptions by default

Claude Code automatically appends a session URL (e.g., https://claude.ai/code/session_...) to every commit message and pull-request description without prompting users. The proposal requests an opt-in prompt during onboarding, while alternatives include an opt-out toggle or removing the URL and relying on the existing “Co-Authored-By: Claude” trailer. The hidden attribution.commit setting can suppress the URL, but it is hard to discover, and git-hook solutions are unreliable in remote environments.