- Add get_tier_by_code and get_tier_id helper methods - Update get_or_create_subscription to set tier_id - Update create_subscription to set tier_id - Update update_subscription to sync tier_id when tier changes - Update upgrade_tier to set tier_id All subscription CRUD operations now maintain the tier_id FK relationship in sync with the tier code string. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>