* Improve shutdown logic of language server
This PR addresses problems mentioned in #7470 and #7729:
- shutting a language server explicitly will not lead to a soft shutdown
- `project/status` endpoint returns the state of the language server
`LanguageServerController` now also signed up for `ClientConnect`
messages. For it to be unambiguous, we need to carry around the port
number of the language server as a way of identifying the right one.
One can now use `project/status` to additionally determine the state of
the language server.
Also relies on a proper fix for #7765.
* changelog
* PR comments
Related to #1153, implements the first part of the integration, without the
parts that use the runner which will be done next.
Temporarily there are two logger implementations - this will be alleviated with
the next part - when and the direct classpath dependency on the language server
is removed.
