Docs - Create Payment Widget API Feature Page

[MantisClone]

Problem

The Payment Widget Button is a key integration option for checkout (distributed as shadcn component), but we have no API Feature page documenting it. Currently using placeholder links in use case pages (Checkout, and future pages).

Proposed Solution

Create /api-features/payment-widget.mdx documenting:

• What Payment Widget Button is (shadcn component, not npm package)
• Installation via shadcn CLI: npx shadcn@latest add "https://request-ui-registry.vercel.app/r/payment-widget-button.json"
• Configuration options and customization
• Integration patterns for different frameworks
• How it uses Request Network API backend
• Link to checkout demo (https://checkout.request.network)
• Playground available at https://checkout.request.network/playground

Considerations

• Should this be called "Payment Widget" or "Payment Widget Button"? (Recommend "Payment Widget Button" for specificity)
• May need to coordinate with web-components repo maintainers for technical accuracy
• Should document Reown AppKit (WalletConnect) integration for wallet connection
• Consider creating separate tutorial for step-by-step integration later
• Currently referenced from Checkout use case page (Issue Docs - Clean up Checkout use case page #33)