Geo: Track bulk action progress in Admin UI

Release notes

When a user launches bulk actions (Resync all, Reverify all) from the Geo admin UI, they do not get feedback (visual or otherwise) of the job's progress. This issue offers a high-level overview of what's needed to allow users to get progress-bar visual feedback when launching such actions.

Problem to solve

How can a background works like the BulkMarkVerificationPendingBatchWorker give feedback to the user?

There are two main problems here:

1. This is a background job, by nature disconnected from the request life-cycle. There is no current backend-to-frontend communication channel in the Geo Admin UI.
2. The background job only marks the verification as pending on the replicators, which will get picked up by the Geo periodic workers.

➡️ The main problem to solve is therefore: enable the Geo periodic workers to recognise which verifications are part of a bulk, and upon completion of each job in the bulk, pass an update to the Rails app. The app can in turn update the front-end.

Proposal

This is yet to be properly defined 🙂

• There is a large backend element in figuring out how to pass progress information to the workers / jobs, as well as back to the front-end serving app.
• There is also a front-end element in receiving the backend progress information.

Intended users

The use of the bulk action (from start to finish, and for each individual worker) should have metrics, but I do not think the progress bar work in itself would benefit from it.

Does this feature require an audit event?

No

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