Driver app needs wallet setup screen in onboarding flow

[variablefate]

After importing an npub, granting permissions, and continuing from the routing tile screen, the driver app should open the wallet setup screen to check for previous wallets.

Currently the wallet setup screen logic exists but isn't wired into the driver onboarding flow.

Expected behavior:

1. Import npub
2. Grant permissions
3. Continue from routing tile screen
4. → Show WalletSetupScreen (checks for previous NIP-60 wallet)
5. Continue to main driver screen