Settings › Backups speaks the home page's language #9708

Next in the design pass after #9433; #9645-#9649, #9688-#9690, #9693 and #9694 cover other pages. Backups is where the owner trusts nothing is lost; it still boxes its sections in cards (backups.ts ~235, ~394, ~467, ~547).

Done looks like:

• [x] The page follows the opening principles of docs/DESIGN.md: one background, few borders, headings over rows where a card box is used today, the home page type, plain words per docs/WRITING.md.
• [x] Any new component class is named in docs/design/areas/<area>.md, never docs/DESIGN.md.
• [x] A test renders the page and asserts the rows-not-boxes shape for the snapshot list, and fails on the current markup.
• [x] bun scripts/design-lint.ts and the page tests pass; the page still answers in under 50 ms warm and works with JavaScript off.

Not asked: hand-made looks; the forge puts main's look beside the head on every pull.

Files: src/web/pages/backups.ts. Risk: the live region (backups-live, data-live) must keep its id and data attributes so live updates still swap it. Brief: a web builder.

Reviewed pull #9754 at its head: ticked The page follows the opening principles of docs/DESIGN.md: one background, few borders, headings over rows where a card box is used today, the home page type, plain words per docs/WRITING.md.; Any new component class is named in docs/design/areas/<area>.md, never docs/DESIGN.md.; A test renders the page and asserts the rows-not-boxes shape for the snapshot list, and fails on the current markup.; bun scripts/design-lint.ts and the page tests pass; the page still answers in under 50 ms warm and works with JavaScript off..