Feature/scan for safes

[Oxbobby]

Summary

Adds on-demand discovery of Safe accounts during account import and changes smart account discovery so smart-account keys are derived only when the user explicitly scans for linked smart accounts.

Changes

• Add Safe discovery helpers that use Safe API Kit to:
  • find Safes by owner address
  • fetch Safe creation/config data
  • return import-ready Safe metadata
• Add AccountPickerController.scanForSafeAccounts(ownerAddrs) to discover Safes for selected owner accounts across enabled Safe-supported networks.
• Track separate loading/completion state for linked smart account scans and Safe scans.
• Make linked smart account discovery explicit/on-demand instead of deriving smart-account-only keys during initial page load.
• Preserve the initial account page as basic EOAs only until smart account discovery is requested, improving hardware wallet flows such as Ledger.
• Refactor Safe import lookup to reuse the new shared getSafeImportInfo helper.
• Treat already-imported Safe accounts as imported with the same keys.
• Update account picker tests for the new on-demand smart account derivation flow