Allow for Write/Delete/Update on Features

### Intro
Thanks for this interesting project! I was coming across the project on my search for an OGC-compliant Webserver. In particular I like the perfect integration with FastAPI. At the moment we are having some custom functionality for CRUD on Geofeatures in our application, but we are aiming to make use of a library such as tipg to have things more generic.

### Question
Meanwhile, as far as I understand tipg is aiming to be "Read-only", meaning there is no Create, Update and Delete. I get the reasoning behind this and in many projects this is fine. As for us we would need full CRUD I was just wondering if you would welcome a contribution implementing Create, Update and Delete for the Features?

(This is just meant to be a hypothetical question at the moment as we have not yet decided using tipg.)