New frontend

[TylerFisher]

WIP draft PR for the new frontend. Thus far:

• Adds django-cotton as a templating engine
• Uses Kelp as a lightweight CSS framework
• Adds a custom map using MapLibre GL, Geoman, Alpine.js, Turf, and PMTiles.

Apologies for the linter cruft. I'll clean that up before anything gets merged.

[mikejcorey]

Thanks for this! Do I view it using the regular python manage.py runserver test server, or is there a different way to view the frontend?