fix(android): keyboard not appearing on first tap for CardField

[meylis1998]

Summary

• Fixes The keyboard does not appear when the card number text field is tapped. #2286: Keyboard doesn't appear when card number text field is tapped on Android (requires multiple taps)

Root Cause

The Android CardField and CardFormField implementations lacked the Listener + Focus widget wrappers that iOS has. This prevented proper touch-to-focus coordination.

Solution

Wrap Android card field widgets with the same Listener + Focus pattern used by iOS:

• Listener intercepts onPointerDown to request focus
• Focus manages focus state and triggers _handleFrameworkFocusChanged
• This invokes native requestFocusFromJS() which shows the keyboard

Changes

• packages/stripe/lib/src/widgets/card_field.dart - Wrapped _AndroidCardField with Listener + Focus
• packages/stripe/lib/src/widgets/card_form_field.dart - Wrapped _AndroidCardFormField with Listener + Focus

Test plan

• Run example app on Android device
• Tap CardField - keyboard should appear on first tap
• Test CardFormField similarly
• Verify iOS still works correctly
• Test autofocus behavior
• Test disabled state (keyboard should not appear)

[jonasbark]

Thank you, looks good!