PoC: Package language-server as a library

[JaroslavTulach]

Recent Hubert's investigations have brought up issue of Api.Runtime envelop serialization and deserialization overhead. It has already been tracked as

• Avoid multiple serialize-deserialize cycles when returning results to Language Server clients #5741

and a possible suggestion to avoid such overhead was outlined in

• Language Server 2.0 #5419

Ultimately that leads to Making Language Server Part of the IDE - that solves the versioning problem. However to get to that we need to move language server code to hosted area - e.g. place it into polyglot/java.

By packaging the language server implementation as an Enso library Standard.Language_Server and bundling it together with the IDE we will always guarantee the he language server protocol version required by the IDE is the same as the one supported by the Standard.Language_Server library.

Tasks

Preview Give feedback

1. Remove dependency of runner on language-server and its libraries - engine-runner shall not depend on language-server #10536
2. Package language-server code into polyglot/java directory of some (maybe Standard.Language_Server or Standard.Visualization library)
3. Change boot sequence to launch such server
4. Make sure the language server code can still send the same messages to runtime.jar

When this is achieved, change the server to call into runtime via builtins.