[BUG]: Contributor Profile fails with HTTP 422: GitHub Search API requires is:issue or is:pull-request

### Bug Description

## Description:
Opening a contributor profile fails to load contribution data and displays:

Failed to fetch contributor details: HTTP_422

### Steps to Reproduce

Steps to Reproduce
- Open OrgExplorer.
- Explore any organization.
- Navigate to Contributors.
- Open any contributor profile.

### Logs and Screenshots

### Environment Details

- OS: Windows 11
- Browser: Google Chrome 150.0.0.0
- Version: v1.0.0-stable
- Deployment: https://orgexplorer.aossie.org
- Authentication: reproduced with a Valid GitHub Personal Access Token
- Reproducible: Yes

### 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 by reproducing the failure from a contributor profile and tracing the GitHub Search API request made while loading contribution data. Check how the search query is built and verify the profile loads successfully without HTTP 422, including contribution results.

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