Inlay Hints in neovim

Thanks @Blue-Berry!

Also, I found that after pinning merlin/lib and ocaml-lsp-server to:

opam pin add merlin https://github.com/ocaml/merlin.git#main
opam pin add merlin-lib https://github.com/ocaml/merlin.git#main
opam pin add ocaml-lsp-server https://github.com/ocaml/ocaml-lsp.git#master

There now is an additional inlay_hint parameter that isn’t in the opam released branch yet, hintFunctionParams.

settings = {
    extendedHover = {enable = true},
    standardHover = {enable = true},
    codelens = {enable = true},
    duneDiagnostics = {enable = true},
    inlayHints = {
        hintPatternVariables = true,
        hintLetBindings = true,
        hintFunctionParams = true
    },
    syntaxDocumentation = {enable = true},
    merlinJumpCodeActions = {enable = true}
}

Additionally I overrode the lsp that is coming from mason in NVIM that is sometimes being invoked by using the command:
cp -f ~/.opam/default/bin/ocamllsp ~/.local/share/nvim/mason/packages/ocaml-lsp/bin/ocamllsp

You can see screenshot of my setup below, I modified the Code Lenses to show up above the functions as well just like in VSCode: