Add React-Admin frontend & Improve dev container

[BigCheeze45]

This PR is a bit big but adds the remaining components needed for the VMS:

• Django REST framework - set this up following tutorial in the docs.
• React-Admin frontend - similarly, set this up following tutorial in the docs.
• Miscellaneous improvements to dev container setup

[tstoyano]

Amazing.

[tstoyano]

Reviewed