Settings: adopt the kit settings pages and rows #78

What to build

The settings surface becomes the kit's settings component: pages and groups of named rows, each row a title, a description, a help line, and one control. Search filters the rows and lands on the page that holds a match.

Today the surface is a hand-built stack of section cards, with a house helper for the card chrome and another for the label-and-help column, and two other views borrow those helpers. Adopting the component removes the house chrome and gives the rows search.

Acceptance criteria

• The settings surface is built from pages and groups: connection, general, limits, sync, tagging, and storage.
• Search filters rows by title and description, lands on the matching page, and produces a sane empty result.
• Every row keeps what it has now: the label, the help sentence, the unit, the accepted bounds, the element id, and the accessible name. Keyboard paths are unchanged — Enter and Space on switches and radios, Up and Down on numeric fields.
• Rows with no kit field type render as custom items and stay keyboard reachable and correctly named: the sign-in method radios, the album-scope radios, the read-only storage paths, and the tag-page link.
• Invalid values are still refused with the same wording, and a save failure still shows its notice without closing the surface.
• The house card and label helpers leave this surface, and the views that borrowed them end up using whichever of this ticket or the diagnostics ticket is left.
• Both themes and the narrowest supported window still lay out every row without clipping a control.

Notes

The kit has no radio field type in the pinned version, so the two radio rows need the custom-item path. Connection state, save results, and the backfill line are read from the existing models; this ticket moves layout, not state.