Create wiki page for Mentor Coordinator duties

### Overview
We need to lay out what the duties of the Mentor Coordinator are and how to do them.

### Action Items
- [ ] to be defined

### Resources/Instructions

The issue names no file, test, or existing wiki page, and its action items are still undefined. Start by reviewing the repository’s wiki and contribution guidance to find where Mentor Coordinator duties belong. Done means a complete, usable page describing the duties and how to carry them out.

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