Add two new import paths to the setup wizard:
- "Importa xpub / xprv": accepts any SLIP-132 key (xpub/ypub/zpub or
xprv/yprv/zprv), auto-detects script type from the version prefix,
and saves a watch-only or fully-spendable HD account accordingly.
- "Importa chiave WIF": accepts one or more WIF private keys (one per
line), goes through script-type selection, and saves an ImportedKeyAccount.
WizardFlowKind enum (New, Restore, ImportXkey, ImportWif) governs which
steps are shown; WizardBack() updated for all four flows. OpenLoaded()
updated to accept IWalletAccount and display wallet kind tags
(watch-only / imported) in the network info line.
Localization keys added for all six languages (it/en/es/fr/pt/de).
ViewModel._account changed from HdAccount? to IWalletAccount?.
Drop the mainnet/testnet/regtest ComboBox from the wizard and fix
Net to always return NetKind.Mainnet. Core profiles and CLI --net
flag are untouched; the wallet file still records the network name.
davide