PR astral-sh#660 (ff130c4) makes an action argument required. This breaks `rye
config --show-path`. This fixes this behavior by requiring any argument,
but showing help when no argument is provided.

fix

Some tests, such as testing rye config, do not require a project,
hence init can be unused.

Add a filter for [RYE_HOME]. This will be used for outputs such as
`rye config --show-path`

We add configuration tests as an integration insta test, as we
want to go through the whole process.