PIN Entry, 2FA, Sending, and Sent Confirmation Screens #47
Description
Implement the multi-step transaction authentication flow. Step 1: PIN entry screen with a 4-digit numeric keypad and biometric option. Step 2: 2FA Auth Code screen with a 6-digit input and numeric keypad. Step 3: loading screen with spinner and transaction summary. Step 4: success screen with checkmark, confirmation message, "View in Explorer" link, and Done button.
Acceptance Criteria:
- PIN screen renders 4 input boxes and a full numeric keypad with backspace and fingerprint icons
- Correct PIN advances to 2FA screen; incorrect PIN shows error feedback
- 2FA screen renders 6 input boxes and numeric keypad
- Valid 2FA code advances to the Sending screen
- Sending screen shows a loading spinner and "Sending… [amount] to [address]" text
- On success, transitions to Sent screen with checkmark animation
- Sent screen shows success message, truncated destination address, "View in Explorer" link, and Done button
- Done button returns user to the home/wallet screen