docs: add Tap to Pay wallet integration guide

[devin-ai-integration]

Summary

Adds a new "Tap to Pay" page under WalletConnect Pay for Wallets with full integration guides for both Android and iOS.

New file: payments/wallets/tap-to-pay.mdx

The page covers:

• Android: NFC dispatch flow (NDEF_DISCOVERED, TECH_DISCOVERED, App Links), manifest setup, NFC interceptor activity, foreground dispatch, and payment processing via WalletKit Pay
• iOS: Background Tag Reading, Universal Links (AASA), CoreNFC manual scan, SceneDelegate handling (warm + cold start), NFC button wiring, and payment processing via WalletKit Pay
• Mermaid sequence diagrams for both "tap from home screen" and "tap from foreground app" flows on each platform
• Step-by-step integration guides using Mintlify <Steps> components
• BETA tag displayed next to the page title in the sidebar navigation

Navigation: Added payments/wallets/tap-to-pay to the "WalletConnect Pay for Wallets" group in both the 2026-02-18 and 2026-02-19.preview version tabs in docs.json.

The page includes an experimental feature callout directing wallet developers to contact support before implementing.

Review & Testing Checklist for Human

• Verify the Tap to Pay page renders correctly in the Mintlify preview deployment
• Check that the "BETA" tag appears next to "Tap to Pay" in the sidebar
• Check that all mermaid diagrams render properly (4 total: 2 Android, 2 iOS)
• Confirm the page appears in the sidebar under "WalletConnect Pay for Wallets" in both API versions
• Review code samples for accuracy (Kotlin/Android and Swift/iOS)

Notes

• Content sourced from the provided nfc-tap-to-pay-wallet-guide.md attachment
• Converted from raw markdown to Mintlify MDX format (frontmatter, <Note> callouts, <Steps> components, code block titles)

Link to Devin session: https://app.devin.ai/sessions/f47ba0be81a345b093191cd1a489558b
Requested by: @mirnab0

[mintlify]

Preview deployment for your docs. Learn more about Mintlify Previews.

Project	Status	Preview	Updated (UTC)
wc-pay-docs	🟢 Ready	View Preview	May 15, 2026, 7:45 AM

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