Provide Auto-Completion for Type Signatures

[Hyalunar]

Futhark does a lot of work to infer the type for bindings and it provides the inferred type via textDocument/hover for LSP-Clients.

I like to have the types inferred as I write. This allows me to refactor something I'm working on without clashing with types I wrote out. Once I consider something done, I will write down the types to avoid confusion for future me.

It is currently possible to hover over the usage (not definition) of a function and copy the inferred type from there, but this is tedious.
Screenshot using futhark lsp in neovim, hover info of a function usage:

Asciinema Recording of the process:

The Language Server could provide a code lens or code action to automatically fill the inferred type.

Reference Screenshot from HLS in neovim with a type signature code lens:

[athas]

I think this would be easy to implement, as the information is already available in the AST. It's just a matter of communicating it across the LSP.