Store onramp user country selection

[ikem-legend]

Summary

This PR enhances the onramp flow by persisting the user's country/region selection in a cookie. When users return to the buy flow, their previously selected country is automatically restored, improving user experience.

Rationale

Users who frequently use the onramp feature shouldn't need to re-select their country each time they initiate a purchase. By storing the selection in a cookie, we provide a smoother, more personalized experience that remembers user preferences across sessions.

Changes

• Added react-cookie dependency and created shared cookie configuration (defaultCookieOptions)
• Wrapped AccountDialog with CookiesProvider in ConnectButton component
• Updated SelectBuyRegionStep to:
  • Read country from panna_user_country cookie on mount (prioritized over browser detection)
  • Save selected country to cookie when user proceeds to next step
• Added comprehensive unit tests for cookie logic (shouldSetCookie, getInitialCountry)
• Refactored siwe-auth.ts to use shared cookie options

Impact

• No breaking changes to existing functionality
• Country selection priority is now: cookie > browser detection > default (US) > first available
• Cookie is set with secure, strict same-site options for security

Testing

• Added 10 new unit tests for cookie-related logic in select-buy-region-step.test.tsx
• Tests cover:
  • shouldSetCookie: determining when to set/update cookie
  • getInitialCountry: priority order for initial country selection
• All 17 tests pass in the test file
• Lint and format checks pass

Screenshots/Video

N/A - Cookie storage is not visible in UI, but behavior can be verified by:

1. Opening the buy flow and selecting a country
2. Closing and reopening the buy flow
3. Observing the previously selected country is pre-filled

Checklist

• Code follows the project's coding standards

• Unit tests covering the new feature have been added

• All existing tests pass

• The documentation has been updated to reflect the new feature

Additional Notes

Cookie name: panna_user_country
Cookie options: { path: '/', secure: true, sameSite: 'strict' }

[Copilot]

Pull request overview

This PR adds cookie persistence for user country/region selection in the onramp flow, allowing users' country preferences to be remembered across sessions. The implementation uses the react-cookie library and introduces shared cookie configuration.

• Added react-cookie dependency and created centralized cookie configuration
• Wrapped AccountDialog with CookiesProvider to enable cookie access
• Updated country selection logic to read from and write to panna_user_country cookie

Reviewed changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
pnpm-lock.yaml	Added react-cookie@8.0.1 dependency and its type definitions
packages/panna-sdk/package.json	Added react-cookie to package dependencies
packages/panna-sdk/src/react/consts/cookies.ts	Created shared cookie configuration with secure defaults
packages/panna-sdk/src/react/components/buy/select-buy-region-step.tsx	Integrated cookie storage for country selection with priority logic
packages/panna-sdk/src/react/components/buy/select-buy-region-step.test.tsx	Added unit tests for cookie helper logic
packages/panna-sdk/src/react/components/auth/connect-button.tsx	Wrapped AccountDialog with CookiesProvider for cookie access
packages/panna-sdk/src/core/auth/siwe-auth.ts	Refactored to use shared cookie configuration

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 6 changed files in this pull request and generated 4 comments.

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.