Migration 028 (tombstone_closed_at) recreates the issues table but was missing the created_by column that exists in schema.go. This caused `SELECT * FROM issues` to fail with column count mismatch on fresh DBs. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>