Co-Authored-By default is inappropriate — stop branding user work

Claude Code automatically appends Co-Authored-By: Claude <noreply@anthropic.com> to every git commit message by default. This is not acceptable.

Users pay for this tool. It is an assistant. It should not be claiming co-authorship of work it was hired to do. This is like a contractor stamping their logo on your house without asking.

In my case, 489 commits were tagged before I noticed. Now I need a full git history rewrite and force push to clean it up.

Request: Remove the default Co-Authored-By behavior entirely, or at minimum make it opt-in rather than opt-out. The tool should not brand user work without explicit consent.