idea: add function to load a vm stack trace into the quickfix window

I was just brainstorming with @natebosch about this idea:

I often use stacktraces to debug issues, I go through each line in the stack trace trying to find some details. I manually convert the source location to jump back in the code, desugaring `package:*` URIs as needed.

It would be great if the vim plugin could support this via some function. The function could let you invoke a command and parse the output, or it could take an input file instead. Not sure how to combine this together with vim-lsc: will the two conflict with each other if there happen to be errors in a file produced from the dart_language_server?

The issue names no files, tests, or entry points. Start by examining the Vim plugin's quickfix handling and how it interacts with vim-lsc, then clarify whether the function consumes command output or an input file. Done means a defined stack-trace parsing workflow that jumps to desugared source locations without conflicting with language-server diagnostics.

Written by the indexing model from the issue text.