chore: groundwork for media purge system

docs/design/source/RenewCMS Screens Back-office.dc.html

@@ -223,6 +223,8 @@ class Component extends DCLogic {
 				Mp({ upload: upT([rowRej, { n: 'notes.pdf', sz: '210 KB', st: 'rej', title: 'notes.pdf isn\'t an image', msg: 'Images can be up to 10 MB. Use a PNG, JPEG, WEBP or SVG image.' }, { n: 'broken.png', sz: '3.0 MB', st: 'rej', title: 'broken.png couldn\'t be read', msg: 'The server couldn\'t read this image. Save it again as a PNG or JPEG, then try again.' }], { title: 'Nothing was uploaded', sub: '3 files were rejected', done: true }), name: 'Upload: rejected files (413, 400)', trigger: 'Type and size are checked in the browser first, so nothing is sent. A server 413 or 400 for a file that got through shows the same row with its own message.' }),
 				Mp({ limited: true, name: 'Upload: too many requests (429)', trigger: 'Rate limited. Retry-After is counted down in the button. It re-enables at zero. Already-added files are kept.' }),
 				Mp({ tab: 'dups', name: 'Duplicates: groups', trigger: 'The Duplicates tab. Groups of identical images side by side, each with its uploader, upload date and "Used in N articles". The suggested copy to keep is the most used, then the oldest.' }),
+				Mp({ tab: 'dups', modal: { k: 'purge' }, name: 'Purge duplicates: confirm', trigger: '"Purge duplicates" in the toolbar, next to the sort menu (in the stacked toolbar on mobile). Opens the same dialog as Settings; every other state is on the Media cleanup board.' }),
+				Mp({ tab: 'dups', member: true, name: 'Duplicates: no purge button (member)', trigger: 'Verified users who are not owner or admin. The "Purge duplicates" button is hidden. "Merge into this one" is unchanged.' }),
 				Mp({ tab: 'dups', dupEmpty: true, name: 'Duplicates: empty', trigger: 'No groups. The Duplicates tab loses its count badge.' }),
 				Mp({ tab: 'dups', modal: { k: 'merge' }, name: 'Merge: confirm', trigger: '"Merge into this one" on floorboards.jpg. The dialog says articles using the other copies will switch to this image and the other copies will be deleted, with the article count.' }),
 				Mp({ tab: 'dups', modal: { k: 'merge', loading: true }, name: 'Merge: in progress', trigger: 'Request in flight. The dialog can\'t be dismissed.' }),