Remove free credits system (signup bonus, daily credits) and B2B organization
credits to simplify the codebase. Credits now only come from purchases or gifts.
Changes:
- Remove freeCreditsRemaining, dailyFreeCredits, lastDailyResetAt from balances
- Remove organizationBalances and creditAllocations tables from schema
- Simplify transaction types to: purchase, usage, refund, gift
- Remove B2B endpoints from credits controller
- Remove checkDailyReset, allocateCredits, deductCredits from service
- Add redeemPendingGifts method to auto-redeem gifts on registration
- Update frontend to remove free credits display
- Add database migration for the changes
- Update all related tests to match simplified system
- Fix LoggerService mock in better-auth.service.spec.ts
- Fix name assertion in auth.controller.spec.ts (empty string fallback)
- Fix createRemoteJWKSet mock in jwt-auth.guard.spec.ts
- Add Grafana dashboard for Auth Service monitoring
- Add 10 auth-specific Prometheus alert rules
- Update production readiness plan to 100% complete
All 199 unit tests passing.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>