Add mutation tools to chat workflow

Problem

Right now, the chat workflow cannot create/edit/write. We did this as a precaution, as well as to collaborate with UX on how best to showcase diffs. We want to be able to try these tools though in order to test them, so we should add them back in the chat workflow behind a feature flag for internal use only. We should also warn users that duo workflow can potentially overwrite any changes they've already made to their code.

Desired Outcome

Chat workflow has access to mutation tools

Implementation Plan

This work should be behind a feature flag