Organization storage dashboard #523
Description
We should show test storage usage to organization admins.
The dashboard should include some basic info, such as:
- A list of problems with their storage usage (optionally sortable by size)
- Total storage used by the organization
For the initial version, we could only account for test ZIP files, and ignore checker files.
Checker files are usually only a few KB, so tracking them may not be worth the extra effort (but open for discussion).
For this, we also need to backfill the old data -> a simple command is enough, no need to put it in migration