feat(core): Add MFA (#4767)

https://linear.app/n8n/issue/ADO-947/sync-branch-with-master-and-fix-fe-e2e-tets

---------

Co-authored-by: कारतोफ्फेलस्क्रिप्ट™ <aditya@netroy.in>

packages/cli/src/Mfa/helpers.ts

@@ -0,0 +1,21 @@
+import config from '@/config';
+import * as Db from '@/Db';
+import { MFA_FEATURE_ENABLED } from './constants';
+
+export const isMfaFeatureEnabled = () => config.get(MFA_FEATURE_ENABLED);
+
+const isMfaFeatureDisabled = () => !isMfaFeatureEnabled();
+
+const getUsersWithMfaEnabled = async () =>
+	Db.collections.User.count({ where: { mfaEnabled: true } });
+
+export const handleMfaDisable = async () => {
+	if (isMfaFeatureDisabled()) {
+		// check for users with MFA enabled, and if there are
+		// users, then keep the feature enabled
+		const users = await getUsersWithMfaEnabled();
+		if (users) {
+			config.set(MFA_FEATURE_ENABLED, true);
+		}
+	}
+};