Reward engine:
- Recurring milestones (every 3 → +7d, every 5 → +14d) instead of one-time
tiers capped at 5; idempotent + transactional grants serialised per
referrer so concurrent qualifications can't double-count.
- Rewards now gated on the referred user's email verification
(afterEmailVerification hook); already-verified referees (OAuth) qualify
at apply time.
- Reward days banked as users.referral_credit_days when the referrer has no
live subscription, consumed on next trial start / activation (no more
silently lost rewards).
- Accurate cumulative rewardDays in stats; getMyReferrals returns referee
name/masked email/status.
Hardening / cleanup:
- onConflictDoNothing makes apply idempotent (no unhandled unique violation).
- Anti-fraud: normalizeEmail blocks self-referral via gmail dot/+tag aliases.
- Collision-safe referral code generation at signup.
- Single apply path (welcome onboarding modal); removed duplicate calls in
register + subscription pages. Input validation on the apply code.
Email verification UX:
- Verification link now lands on a dedicated /email-verified confirmation
page instead of the deep-linked VIN/search page.
Schema: referrals.status + qualified_at, users.referral_credit_days (0009).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
