Freezor/Refactor MainLayout and NavMenu

[Freezor]

Description

This PR includes several changes to enhance the MainLayout and NavMenu components.

Motivation and Context

The motivation behind these changes is to improve the structure, readability, and maintainability of the MainLayout and NavMenu components. These changes aim to address concerns related to separation of concerns, code clarity, and consistency.

Fixes # (issue)

Type of change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] This change requires a documentation update

How Has This Been Tested?

These changes have been manually tested by reviewing the updated components and verifying their behavior. Automated unit tests have been added to ensure the correctness of the components' functionality.

Screenshots (if appropriate):

Checklist:

• [x] My code follows the style guidelines of this project
• [X] I have commented my code, particularly in hard-to-understand areas
• [X] I have made corresponding changes to the documentation
• [x] I have added tests that prove my fix is effective or that my feature works

[Freezor]

@AlexanderWollbrink I cannot assign you directly to the PR review 😞