feat: replace moryflow redemption proxy with native implementation

[dvlin-dev]

Summary

• Replace the proxy-to-anyhunt redemption module with a native moryflow implementation that directly operates on the moryflow database
• Add GET /admin/redemption-codes/config endpoint to both moryflow and anyhunt servers, making tier options backend-driven
• Admin frontend now fetches tier options from config endpoint instead of hardcoding them, enabling a single codebase to serve both deployments

Changes

Moryflow server (apps/moryflow/server/)

• Add RedemptionCode and RedemptionCodeUsage Prisma models with @@unique([redemptionCodeId, userId]) per-account constraint
• Implement RedemptionService with full CRUD + atomic redeem (concurrent-safe updateMany with lt: maxRedemptions)
• Add user-facing RedemptionController (/app/redemption-codes/redeem)
• Add AdminRedemptionCodesController with config endpoint and CRUD
• Integrate with CreditService (tx-aware) and ActivityLogService
• Delete proxy module (redemption-proxy.controller.ts, redemption-proxy.service.ts)

Anyhunt server (apps/anyhunt/server/)

• Add GET /admin/redemption-codes/config endpoint returning { tiers: [BASIC, PRO, TEAM] }

Admin frontend (apps/anyhunt/admin/www/)

• Remove hardcoded MEMBERSHIP_TIER_OPTIONS
• Add getRedemptionCodeConfig() API + useRedemptionCodeConfig() hook
• CreateRedemptionCodeDialog fetches tiers from backend config
• membershipTier schema changed from z.enum() to z.string().min(1)

Deployment note

Run prisma migrate deploy on the moryflow database to create the new RedemptionCode and RedemptionCodeUsage tables.

Test plan

• Moryflow server: tsc --noEmit passes (verified locally)
• Moryflow server: lint passes with 0 errors (verified locally)
• Anyhunt server: tsc --noEmit passes (verified locally)
• Admin frontend: build succeeds (verified locally)
• Run Prisma migration on staging database
• Verify admin create/list/edit/delete redemption codes
• Verify user redeem flow from PC app
• Verify per-account single-use constraint
• Verify concurrent redemption safety

---

[dvlin-dev]

All 3 review comments addressed in commit d50de09:

1. Migration file — Added prisma/migrations/0002_add_redemption_codes/migration.sql with CREATE TYPE, tables, indexes, and foreign key. prisma migrate deploy will create the tables automatically.

2. membershipDays default bleed — Removed .default(30) from the DTO. Default now applied conditionally in service: dto.type === 'MEMBERSHIP' ? (dto.membershipDays ?? 30) : null. CREDITS codes correctly store membershipDays: null.

3. OpenAPI exposure — Split into RedemptionModule (public /app/) and AdminRedemptionModule (internal /admin/). PUBLIC_API_MODULES only contains RedemptionModule, INTERNAL_API_MODULES only contains AdminRedemptionModule. Admin endpoints no longer appear in the public OpenAPI doc.