Test cases for FEPs

[helge]

@helge

My current plan is to start a repository for myself with features related to FEPs. If interest arises, people will be able to contribute / turn it into a more official process.

Just to check that nobody has any objections to this, before I remove the demo folder from fep-4adb.

New home for tests: helge/fediverse-features: Gherkin Features for BDD in the fediverse - fediverse-features - Codeberg.org