add a clear usage guidelines for logo spacing, sizing, and minimum clear space

The Base Brand Kit provides high-quality visual assets, but it does not clearly document rules around logo spacing, sizing, and minimum clear space. Without these guidelines, consumers may unintentionally misuse the brand assets in ways that reduce visual consistency.

### Problem Description
Teams using the Brand Kit may be unsure about:
- minimum clear space around logos
- acceptable minimum and maximum logo sizes
- how logos should be placed relative to other UI elements
- differences between acceptable usage in web, mobile, and print contexts

This can lead to inconsistent or incorrect brand presentation.

### Expected Behavior
- Consumers should have clear guidance on how to correctly use Base logos.
- Brand usage rules should be easy to understand and quick to reference.
- Guidelines should reduce the risk of improper logo placement or scaling.

### Steps to Reproduce
1. Open the Base Brand Kit repository.
2. Review available assets and documentation.
3. Attempt to place a logo in a new design without additional guidance.
4. Notice the lack of explicit spacing and sizing rules.

### Proposed Solution
- Add a short “Logo Usage Guidelines” section to the documentation.
- Clearly define:
- minimum clear space around logos
- recommended minimum and maximum sizes
- examples of correct and incorrect usage
- Use simple diagrams or annotated images where helpful.

### Acceptance Criteria
- Documentation clearly explains logo spacing and sizing rules.
- Examples make correct vs incorrect usage easy to understand.
- No changes are made to existing logo assets.
- Guidelines are concise and easy to maintain.