Refactor of authentication code. Added configuration file selectable authentication method. Selectable from built-in Azure Identity, and custom PCA using MSAL.

src/types.ts

@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: MIT
+
+export type AuthConfig = {
+  tenantId: string;
+  clientId: string;
+};
+
+export type Config = {
+  activeAccountUpn: string | undefined;
+  authMode: string;
+};