Export functionality

Any updates on this Issue

deciphered → changed the visibility of the branch feature/3284680-export_csv to hidden.

deciphered → changed the visibility of the branch 1.0.x to hidden.

I've added a basic CSV export as required for an integration.

It adds a route: /admin/reports/audit-trail/export.
It adds a link to "Export CSV" on the overview page.
It adds the applied filters to the Export CSV link.

deciphered → changed the visibility of the branch 1.0.x to active.

I refactored the PR to add support for Batching of the export due to the large amount of data that can be contained on a site.

It still needs work to improve the UX, as the file is downloaded at the end of the batch process, and not redirected back to the overview form.