Support for inlay hints

[thomasfinstad]

It seems the LSP has added support for inlay hints, it would be great if the extension also would add support.

[anmonteiro]

These should be supported xref ocaml/ocaml-lsp#1159

[voodoos]

🤔 it indeed looks like inlay-hints are not working anymore, but they should be. They should be controlled by the editor-wide settings Editor › Inlay Hints: Enabled.