Duo Chat - Add Local Files to Chat
## Problem to solve
From: https://gitlab.com/gitlab-org/gitlab/-/issues/520305+
Currently we don't allow local files to be uploaded into Duo Chat. Users may want to add in files for a number of reasons including asking for summaries, adjustments, increasing context etc (assumptions).
More details can be found here: https://www.youtube.com/watch?v=KooqHQtpUao
### UX Proposal
* Allow users to drag and drop or copy and paste files into Duo Chat's input box.
* Allow Duo Chat to interact with these files.
### Open Questions
* What are the main use cases for users to paste files into Duo Chat on Web?
* What file types do we want to allow? Which ones do we want to disallow?
* Should there be additional visual enhancements here (when dragging - the UI changes, adding in an attachment button).
* How do we let users know which files are un-allowed when they attempt to upload something?
issue