Resolve "Pass through Compiler errors/warnings in Language server"

Closes #22 (closed)
Closes #18 (closed)

requires clean-lsp!1 (merged)

TODO:

• handle all errors
• documentation
• add automatic test (see https://gitlab.com/top-software/clean-lsp/-/blob/main/example/test.sh for inspiration how to input data to the language server and https://gitlab.com/clean-and-itasks/abc-interpreter/-/blob/master/test/interpreter/run_tests.sh for a way to compare expected with actual output of an executable)