What does this PR do?

Adds LawPay payment integration for Cal.com, enabling legal professionals to accept payments through their LawPay/AffiniPay merchant accounts.

• Fixes #11340
• /claim #11340

Implementation Details

This PR follows the existing PayPal payment app pattern and implements:

• OAuth 2.0 flow for connecting LawPay merchant accounts
• PaymentService implementing IAbstractPaymentService interface
• API endpoints: add, callback (OAuth), webhook
• UI components: EventTypeAppCard and Settings for price configuration
• LawPay API client for charges, refunds, and void transactions

Files Added (18 files)

packages/app-store/lawpay/
├── config.json, package.json, index.ts, zod.ts
├── api/ (add.ts, callback.ts, webhook.ts)
├── lib/ (LawPay.ts, PaymentService.ts, PaymentService.test.ts)
├── components/ (EventTypeAppCardInterface.tsx, EventTypeAppSettingsInterface.tsx)
├── pages/setup/_getStaticProps.tsx
└── static/icon.svg

Mandatory Tasks (DO NOT REMOVE)

• I have self-reviewed the code (A decent size PR without self-review might be rejected).
• I have updated the developer docs in /docs if this PR makes changes that would require a documentation change. N/A - App store apps are self-documented.
• I confirm automated tests are in place that prove my fix is effective or that my feature works.

How should this be tested?

Environment Variables

Add to .env or Admin Settings:

LAWPAY_CLIENT_ID=your_client_id
LAWPAY_CLIENT_SECRET=your_client_secret

Test Steps

1. Run yarn app-store:build to generate app metadata
2. Go to Apps → Search “LawPay” → Click Install
3. Complete OAuth flow with LawPay sandbox account
4. Go to Event Types → Select an event → Enable LawPay payment
5. Set price (e.g., $50 USD)
6. Open booking page and verify payment option appears
7. Complete a test booking with payment

Test Credentials

Use LawPay Sandbox for testing:

• Test card: 4242424242424242
• Any future expiry, any CVV

Checklist

• I have read the contributing guide
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have checked if my changes generate no new warnings
• My PR is appropriately sized (18 files, ~760 lines)