feat: email verification, merchant/store password reset, seed gap fix

- Add EmailVerificationToken and UserPasswordResetToken models with migration
- Add email verification flow: verify-email page route, resend-verification API
- Block login for unverified users (EmailNotVerifiedException in auth_service)
- Add forgot-password/reset-password endpoints for merchant and store auth
- Add "Forgot Password?" links to merchant and store login pages
- Send welcome email with verification link on merchant creation
- Seed email_verification and merchant_password_reset email templates
- Fix db-reset Makefile to run all init-prod seed scripts
- Add UserAuthService to satisfy architecture validation rules
- Add 52 new tests (unit + integration) with full coverage

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/modules/billing/tests/integration/test_store_routes.py

@@ -67,6 +67,7 @@ def store_full_setup(db, store_platform):
         hashed_password=auth.hash_password("storepass123"),
         role="store",
         is_active=True,
+        is_email_verified=True,
     )
     db.add(owner)
     db.commit()