feat(mui): kit — Tabs/TabPanel + Pagination

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/admin/ui/index.ts

@@ -12,3 +12,6 @@ export type { SelectOption } from "./Select";
 export { default as StatusChip } from "./StatusChip";
 export { CheckboxField } from "./Checkbox";
 export { default as Alert } from "./Alert";
+export { Tabs, TabPanel } from "./Tabs";
+export type { TabDef } from "./Tabs";
+export { default as Pagination } from "./Pagination";