Feat: Percentage for Ram Usage

I personally really like having a percentage of my ram being used so I cloned macmon and added the percentage. If this is something there would be interest in having I would be happy to open a PR. Here's a screenshot of what it looks like.

<img width="2490" height="2656" alt="Image" src="https://github.com/user-attachments/assets/0d8e110e-2f15-4469-90a1-07c89243bf6c" />