[BUG]: Contributor Intelligence returns HTTP 422 when fetching contributor details

### Bug Description

The Contributor Intelligence page fails to fetch contributor details and displays:

> Failed to fetch contributor details: HTTP 422

The GitHub API request works correctly when executed manually with the same query and authentication token, but the request made from the web application returns `422 Unprocessable Content`.

### Steps to Reproduce

1. Open the Contributor Intelligence page.
2. Search for the GitHub username `priyanshunitr`.
3. Select the organization `AOSSIE-Org`.
4. Use the default reporting window.
5. Open DevTools → Network.
6. Observe the GitHub API requests.

### Logs and Screenshots

### Environment Details

### Environment

- OS: Windows 10/11
- Browser: Brave 153.0.0.0
- Device: Desktop
- GitHub API: REST API (`api.github.com`)
- Application: AOSSIE Org Explorer

### Impact

High - Major feature is broken

### Code of Conduct

- [x] I have joined the [Discord server](https://discord.gg/hjUhu33uAn) and will post updates there
- [x] I have searched existing issues to avoid duplicates

Start on the Contributor Intelligence page and reproduce the request for `priyanshunitr` in `AOSSIE-Org` using the default reporting window. Inspect the failing GitHub API request in DevTools → Network and compare its parameters and authentication with the manually successful request; done means contributor details load without HTTP 422.

索引モデルが issue の本文から書いたものです。