Faster admin lists and collection browsing by variant

Faster admin lists

Every list table in admin picked up numbered pagination with pending indicators, optimistic updates for deletes, bulk actions and module toggles, and loading skeletons shaped like the rows they stand in for. Table search stays mounted and responsive as you type, so working through a few thousand products feels like a local app instead of a round trip per keystroke.

Collection browsing by variant

Collections gained a products endpoint and browse one card per variant, so a collection of shirts shows each colour as its own card rather than hiding them behind a single entry.

Also shipped

Domains settings leads with connecting a domain — the page opens on the action most merchants came for instead of burying it below the list

Fixes

[admin]Make sidebar group identity and active state consistent
[admin]Optimistic-list edge cases and streaming for the remaining lists
[admin]Pagination a11y and prefetch, URL-driven hub tabs
[admin]Read the URL at call time in search and filter controls
[admin]Replace the remaining native confirms with AlertDialog
[admin]Stop reporting success on failed mutations
[domains]Keep unpublished stores' custom domains off the storefront
[domains]Revalidate the whole settings subtree and return checkout to /buy
[i18n]Close audited namespace gaps and trim the admin root page
[support]Mark cases read from a client mount, not during render