fix: skip backup warning after wallet restore

[jvsena42]

Fixes #669

This PR sets backupVerified to true when a wallet is successfully restored, preventing the unnecessary backup warning sheet from appearing after restore.

Description

When a user restores a wallet using their recovery phrase, they clearly have access to their backup. The app was incorrectly showing the "Wallet Backup" bottom sheet after restore because backupVerified remained false. This PR adds an onSuccess handler to the restoreWallet function that marks the backup as verified.

Preview

Screen_recording_20260129_072648.webm

QA Notes

1. Restore wallet flow

1. Wipe the app data or use a fresh install
2. Tap "Restore wallet"
3. Enter a valid 12-word recovery phrase
4. Complete the restore process
5. Verify the "Wallet Backup" bottom sheet does NOT appear

2. New wallet flow (regression)

1. Wipe the app data or use a fresh install
2. Create a new wallet
3. Verify the "Wallet Backup" suggestion still appears (expected behavior for new wallets)

[claude]

Code review

No issues found. Checked for bugs and CLAUDE.md compliance.

[ovitrif]

lgtm with one nit