aa33b7d271
Phase 1 of multi-account support. Move account types to commons/commonMain so both Android and Desktop share the same data model: - SignerType sealed class (Internal, Remote, ViewOnly) - AccountInfo data class (npub, signerType, isTransient) - AccountStorage interface (loadAccounts, saveAccount, etc.) Desktop AccountManager now imports SignerType from commons instead of defining its own. All existing tests updated with new import path. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>