refactor app configuration and improve Google OAuth handling; update .gitignore and enhance test documentation

TEST/testGooglePhotosAPI.js

@@ -1,22 +1,23 @@
-/**
- * Google Photos OAuth & API Test
- *
- * Usage:
- *   node TEST/testGooglePhotosAPI.js <ACCESS_TOKEN>
- *   GOOGLE_ACCESS_TOKEN=ya29.xxx node TEST/testGooglePhotosAPI.js
- *
- * How to get a token for manual testing:
- *   1. Go to https://developers.google.com/oauthplayground
- *   2. Select "Photos Library API v1" → photoslibrary scope
- *   3. Authorise the API
- *   4. Exchange the authorization code for tokens
- *   5. Copy the access token and pass it to this script
- *
- * Tests:
- *   1. Validates the token against the userinfo endpoint
- *   2. Lists media items from Google Photos
- *   3. Lists albums from Google Photos
- */
+// Google Photos API Test
+//
+// Usage:
+//   node TEST/testGooglePhotosAPI.js <ACCESS_TOKEN>
+//   GOOGLE_ACCESS_TOKEN=ya29.xxx node TEST/testGooglePhotosAPI.js
+//
+// Getting a token from OAuth Playground (https://developers.google.com/oauthplayground):
+//   1. Click the gear icon → check "Use your own OAuth credentials"
+//   2. Enter your Client ID and Client Secret from Google Cloud Console
+//   3. In the left panel select ALL of these scopes:
+//        https://www.googleapis.com/auth/photoslibrary
+//        https://www.googleapis.com/auth/photoslibrary.appendonly
+//        https://www.googleapis.com/auth/userinfo.email
+//        https://www.googleapis.com/auth/userinfo.profile
+//   4. Click "Authorize APIs" and sign in with your test Google account
+//   5. Click "Exchange authorization code for tokens"
+//   6. Copy the Access token (starts with ya29.) and pass it here
+//
+// Note: if you only see 403 PERMISSION_DENIED, the token was issued without
+// the photoslibrary scope — go back and re-authorise with all scopes above.
 
 const API_BASE = 'https://photoslibrary.googleapis.com/v1';
 const USERINFO_URL = 'https://www.googleapis.com/oauth2/v2/userinfo';