VS Code Silently Tags Commits with Co-Authored-by Copilot Even Without AI Usage

What Happened

GitHub PR #310226 revealed that VS Code appends Co-Authored-by: GitHub Copilot to commit messages even when no Copilot feature was used. The story hit near the top of Hacker News with over 680 points.

The Broader Issue

Co-authorship metadata carries legal meaning in open-source projects. When an AI tool inserts itself into authorship records without explicit action, it pollutes that signal. Developers are demanding opt-in rather than opt-out for AI attribution in commits.