Can I vibe code Referral Candy?

Build a full-stack Node.js/TypeScript Shopify app that replaces ReferralCandy's core referral tracking, fraud prevention, and reward engine using the Shopify GraphQL Admin API.

DATA MODEL (PostgreSQL via Prisma):
1. Merchant: id, shopifyDomain, accessToken, status.
2. Campaign: id, merchantId, rewardTypeReferrer (STORE_CREDIT, CASH, COUPON), rewardValueReferrer, rewardTypeReferee (PERCENTAGE, FIXED_AMOUNT), rewardValueReferee, minimumSpend.
3. Customer: id, merchantId, shopifyCustomerId, email, uniqueReferralCode.
4. ReferralLink: id, customerId, code, clicksCount.
5. ReferralEvent: id, campaignId, referrerCustomerId, refereeEmail, shopifyOrderId, orderTotal, status (PENDING, APPROVED, REJECTED), rejectionReason.

CORE WORKFLOWS & INTEGRATIONS:
1. Post-Purchase Widget & Link Generation:
   - Use Shopify App Bridge and Checkout Extensions to show a post-purchase referral block on the thank-you page.
   - Automatically create a unique share link (e.g., `store.com?ref=CODE`) for the logged-in or purchasing customer.

2. Referee Attribtion & Checkout Discount:
   - When a visitor lands on `?ref=CODE`, store the referral token in a secure HTTP-only cookie.
   - Inject a Shopify Theme App Extension banner displaying the referee's discount code.
   - Automatically apply a discount code to the cart using Shopify's Storefront API or Discount Coupons API.

3. Order Webhook Processing (`orders/create` and `orders/paid`):
   - Listen to `orders/paid` webhooks. Parse cart discount codes or attribution cookies.
   - If a valid referral token is detected, match the referee's order to the `ReferrerCustomer`.
   - Record a `ReferralEvent` with status `PENDING`.

4. Anti-Fraud & Reward Fulfillment Logic:
   - Fraud Checks: Flag order if `refereeEmail` equals `referrerCustomerId.email`, if shipping address matches referrer address, or if multiple orders originate from the same IP address within 1 hour.
   - Reward Processing: If approved after the return window (e.g., 14 days delay via scheduled worker), trigger reward:
     - STORE_CREDIT: Call Shopify GraphQL API `mutation customerUpdate` or issue a Shopify Gift Card / Store Credit balance.
     - COUPON: Generate a unique single-use discount code for the referrer using Shopify GraphQL `discountCodeBasicCreate`.

OUT OF SCOPE:
- Native iOS/Android mobile SDKs.
- Complex multi-tiered MLM affiliate structures.
- Built-in email marketing automation (delegate all transactional emails to Klaviyo via webhooks).

FAILURE MODES TO HANDLE:
- Webhook duplicate delivery: Ensure idempotency by indexing `shopifyOrderId` uniquely in `ReferralEvent`.
- Rate limits on Shopify GraphQL API: Use a queueing system (BullMQ + Redis) for discount generation and API updates.

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