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

src/cli/commands/list-app-grants.ts

@@ -1,8 +1,7 @@
 // SPDX-License-Identifier: MIT
 
 import { listAppGrants } from "../../graph/app.ts";
-
-import { getGraphClientFromPublicConfig } from "./shared.ts";
+import { getGraphClient } from "../../graph/index.ts";
 import type { CommandValues } from "./types.ts";
 
 export function usageListAppGrants(): string {
@@ -17,6 +16,6 @@ export async function runListAppGrantsCommand(values: CommandValues): Promise<un
     throw new Error("--app-id is required for list-app-grants");
   }
 
-  const { client } = await getGraphClientFromPublicConfig();
+  const client = await getGraphClient();
   return listAppGrants(client, values["app-id"]);
 }