feat: moved theme toggle next to search bar

[vinayak19th]

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Improvement (refactoring and improving code)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Description

New Feature:

1. Integrated the new Bootstrap icons to add a large range of free icons to access
2. Added code to make the mode-toggle button change icons based on current theme

Improvement:

1. Moved the mode-toggle button from the sidebar to the top-bar, right next to the search bar for easier access

Additional context

Here is an image
Light mode:

Dark mode: