Migration 028 lacked an idempotency check, causing it to fail on databases where the migration had already been applied. The migration would attempt to copy data from issues to issues_new, but both tables had the same CHECK constraint, causing the insert to fail. Added check for "status = 'tombstone'" in the table schema to detect if the migration has already been applied and skip if so. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>