Follow-up from "Add a button to export CSV data": persist storage to DB

The following discussion from !26838 (merged) should be addressed:

• @markrian started a discussion: (+2 comments)

  Not blocking: While persisting to local storage is fine, especially for an MVC, the UX could be improved by instead persisting to the database via user_callouts_helper. This way, the state of the popover will persist across all browsers (or the same browser after a localStorage.clear()) for the user.

  See !22117 (merged) for an example of how to do that. There's also a video which goes through another implementation: https://www.youtube.com/watch?v=wJmI4tA92L8.

  That said, it's a fair bit more code for a marginal UX improvement, especially when you have to pass through a handful of values from the backend to a descendant component 🤷

  With all that said, assuming you'll keep this localStorage implementation, I'd recommend that you open a follow-up issue to track clearing up this data for when the popover gets removed.

  Thoughts?