feat(packages): add standalone auth and payment

packages/auth/src/ui/auth.models.ts

@@ -0,0 +1,19 @@
+import { AuthSession } from '../telegram/models/session.model';
+
+export type AuthMode = 'customer' | 'admin';
+export type AuthMethod = 'qr' | 'credentials' | 'yandex';
+export interface CredentialLogin { login: string; password: string; }
+export interface AuthResult {
+  method: AuthMethod;
+  mode: AuthMode;
+  session: AuthSession;
+  accessToken?: string;
+  refreshToken?: string;
+}
+export interface ExternalAuthStart { attemptId: string; authorizationUrl: string; }
+export interface AuthFailure {
+  method: AuthMethod;
+  code: 'configuration' | 'invalid_credentials' | 'backend' | 'popup_blocked' | 'expired';
+  message: string;
+  cause?: unknown;
+}