feat(card): wire Add Funds to unified ramp buy from card home

[amitabh94]

Description

Wires Card Add Funds to unified ramp buy via useRampNavigation / cardFundingTokenToRampIntent, with buyFlowOrigin: 'cardHome' for BuildQuote analytics. Adds cardHome to BuyFlowOrigin and handles Token not available modal navigation back to the Card tab using typed stack navigation (StackNavigationProp<ParamListBase>). Depends on PR 1 (feat/ramp-navigate-to-buy-foundation); this branch stacks that commit so it can merge after PR 1 or be rebased once PR 1 lands.

Follow-up (not in this PR): NativeFlow hoist, sell-only aggregator, and Deposit removal remain future phases when code exists.

Changelog

CHANGELOG entry: Improved Card Add Funds flow to use unified ramp buy routing when applicable.

Related issues

Fixes: N/A

Manual testing steps

Feature: Card Add Funds to unified buy

  Scenario: open unified buy from card add funds
    Given a wallet with Card home and ramps enabled
    When the user opens Add Funds on Card and chooses deposit/buy
    Then unified buy opens with the expected token context

  Scenario: token unavailable from card-originated buy
    Given the user started buy from card home
    When the token unavailable modal appears and the user changes token
    Then navigation returns to the Card home tab as expected

Screenshots/Recordings

Before

After

Pre-merge author checklist

• I've followed MetaMask Contributor Docs and MetaMask Mobile Coding Standards.
• I've completed the PR template to the best of my ability
• I've included tests if applicable
• I've documented my code using JSDoc format if applicable
• I've applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Performance checks (if applicable)

• I've tested on Android
  • Ideally on a mid-range device; emulator is acceptable
• I've tested with a power user scenario
  • Use these power-user SRPs to import wallets with many accounts and tokens
• I've instrumented key operations with Sentry traces for production performance metrics
  • See trace() for usage and addToken for an example

For performance guidelines and tooling, see the Performance Guide.

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

[github-actions]

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[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
94.9% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud