feat: use Deno to format parts of a document

[KnorpelSenf]

Problem

I use the vim emulation in VS Code and I would like to indent the current line correctly by typing == in normal mode. However, this would require Deno to be able to format the current line only, rather than formatting the entire document.

Solution

I would like the Deno extension to be able to format selections/parts of a document so that it can fix indenting for the current line.

This might require prior adjustments to the LSP/dprint, but I felt like this is the best place to report it.