Cache total file size/count

[hectorcorrea]

Calculating the total file size and total file count is slow for large datasets (e.g. datasets with 20-40K files). We should consider caching that information in the Work table along with the last date the values were updated. For example:

work.total_file_size = 1234559
work.total_file_count = 23000
work.total_file_as_of = '2024-11-21 14:00:00'

The process that updates the UploadSnapshot could automatically refresh those values every time it checks for adds/deletes/modifications. That process runs in the background.

The UI could display a little information icon next to the total file size and total file count indicating that the values displayed are current as of the stored data. In the vast majority of cases the values will be up to date, if there is any doubt, the user would be able to click on the information icon to confirm if they are too old (e.g. if a new file was just added but it does not show in the count or size)

See also #1989