Document the payment sequence

[mikenikles]

sequenceDiagram
    autonumber

    participant /dashboard
    participant PaymentProvider as Payment Provider
    participant /api/billing/webhooks/preorder
    participant PostgreSQL

    link /dashboard: Source @ https://github.com/WebstoneHQ/platform/blob/main/services/website/src/routes/dashboard.svelte
    link PaymentProvider: Website @ https://paddle.com/
    link /api/billing/webhooks/preorder: Source @ https://github.com/WebstoneHQ/platform/blob/main/services/website/src/routes/api/billing/webhooks/preorder.ts

    Note over /dashboard: User clicks "Enroll now!"
    /dashboard->>PaymentProvider: Display the Overlay Checkout
    Note over PaymentProvider: User completes payment
    PaymentProvider->>/api/billing/webhooks/preorder: POST request with order information
    /api/billing/webhooks/preorder->>PostgreSQL: Persist payment information