Migrate to LiteStar and use HTMX responses

[spwoodcock]

This would involve a total rewrite of FMTM

• We are moving reactive in-the-field functionality to the mapper frontend (which uses Svelte).
• The management portion of FMTM should be relatively simple, and would significantly improve it's maintainability long term by using HTMX.
• LiteStar is a great successor to FastAPI that support HTMX responses.
• We should consider this in 1-2 yrs once FMTM reaches better maturity and adoption.