[ENHANCEMENT]: Improve difficulty selector UI for better clarity

### Feature and its Use Cases

Currently, the difficulty selector displays options like "Easy Difficulty" within the dropdown.
This mixes the label and value, which reduces clarity.

Proposed change:
Add a separate label: "Difficulty"
Keep dropdown options as: "Easy", "Hard"

### Additional Context

Why:
- Improves readability
- Aligns with standard UI patterns
- Makes it easier to extend (e.g., Medium)

### 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