Request department and staff scopes for Workforce OAuth token

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/workforce.js

@@ -31,6 +31,7 @@ async function getWorkforceToken() {
       grant_type: 'password',
       username: creds.email,
       password: creds.password,
+      scope: 'me department staff',
     }).toString(),
     signal: AbortSignal.timeout(10000),
   })