ellipsis for inlay-hint

[ofzo]

Auto inferred types can be long in some cases, especially type parameters with paradigms, which will make the inlay hint very distracting to code readers, this PR will collapse the display for inlay hints longer than 20 characters

before:

after:

[poliorcetics]

1. Using <...> as the wrapper for generics may be good for most languages, but it won't work for Go for example, so this has to be configurable by language
2. This should be an option, I have never wanted shorter inlay hints in my usage of helix
3. This is reconstructing the regex for each hint, on each LSP call. It should instead put the regex in a static OnceCell (mapping per language, see 1.) and reused

[ofzo]

1. Using <...> as the wrapper for generics may be good for most languages, but it won't work for Go for example, so this has to be configurable by language
2. This should be an option, I have never wanted shorter inlay hints in my usage of helix
3. This is reconstructing the regex for each hint, on each LSP call. It should instead put the regex in a static OnceCell (mapping per language, see 1.) and reused

You're right, I've taken a page from vscode and simplified this capability by removing the language differences and just intercepting to the maximum extent possible, and supporting configuration.