doc: Use the doxygen awesome theme

[realstealthninja]

Description of Change

Our doxygen website is fine but it needs a touch of modernity, I've added the doxygen-awesome theme with a few extensions.

Main changes

• added doxygen theme
• reduced reliance on cmake for doxygen configs
• use doxyfile for doxygen config
• add favicon and project icon

comparison

old	new

Checklist

• [x] Added description of change
• [x] Added file name matches File name guidelines
• ~[ ] Added tests and example, test must pass~
• ~[ ] Added documentation so that the program is self-explanatory and educational - Doxygen guidelines~
• [x] Relevant documentation/comments is changed or added
• [x] PR title follows semantic commit guidelines
• [x] Search previous suggestions before making a new one, as yours may be a duplicate.
• [x] I acknowledge that all my contributions will be made under the project's license.

Notes: