Add simpler development environment

Currently using the website in docker with a fully started faf-stack is not the simplest thing.
since the website can also run with the services of xyz, this should be the preferred way for new developers.

Tasks:
- can we share "secrets" of the xyz in the repo? @Brutus5000
- updating the readme (maybe even removing the local/fafstack install chapter)
- testing the "ease" of startup from scratch with some devs we can find