PR: Fix Onedrive Provider to Use Microsoft Graph API Properly

[urashidmalik]

📦 Fix OneDrive Provider to Use Microsoft Graph API

✨ Summary

This PR updates the onedrive provider in goth to use the Microsoft Graph API (https://graph.microsoft.com/v1.0/me) instead of the deprecated Live Connect API (https://apis.live.net/v5.0/me).

It resolves issues where OneDrive OAuth succeeded but fetching user info returned 401 Unauthorized errors.

📋 Motivation

• Microsoft's Live Connect API is deprecated.
• Microsoft Graph is the official and future-proof API for authentication and user data.
• Users were unable to fetch their email and basic profile after OAuth login.
• This change improves compatibility for both Personal Microsoft Accounts and Work/School accounts.

🔥 Changes

• Updated endpointProfile to https://graph.microsoft.com/v1.0/me.
• Modified FetchUser method:
  • Properly sets Authorization: Bearer <access_token> in headers.
  • Parses response fields:
    • id → UserID
    • mail or fallback to userPrincipalName → Email
    • displayName → Name
  • Improved error handling to print HTTP status and body content when failing to fetch profile.
• No changes required for the existing onedrive_test.go tests (as they test BeginAuth and Session loading only).

🧪 Testing

• ✅ Manually tested full OAuth flow:
  • Authentication redirect.
  • Consent screen.
  • Successful code exchange.
  • Fetching email and profile using Microsoft Graph API.
• ✅ Tested with:
  • Microsoft personal accounts (e.g., Outlook, Hotmail).
  • Azure Active Directory accounts (Office 365/Work accounts).

🚀 Notes

• No API breaking changes for existing users of the goth library.
• Only affects onedrive provider.
• Future unit tests can be added to cover the FetchUser parsing more deeply if needed.

🛡️ This ensures full compatibility with Microsoft's current API standards for authentication and user data access.