milestone 32: task-shaped configuration, file mode as a rendering, config status api

admin/src/ui/Tabs.tsx

@@ -25,6 +25,13 @@ interface Props {
 	/** The tab list's accessible name. */
 	label: string;
 	tabs: readonly TabSpec[];
+	/**
+	 * The open tab, when a caller owns the selection — the configuration pages
+	 * keep it in the URL. Omit both of these to let RAC hold the state, which
+	 * is what a tab set with no linkable identity wants.
+	 */
+	selectedKey?: string;
+	onSelectionChange?: (key: string) => void;
 }
 
 const styles = stylex.create({
@@ -73,9 +80,13 @@ const styles = stylex.create({
 	},
 });
 
-export default function Tabs({ label, tabs }: Props) {
+export default function Tabs({ label, tabs, selectedKey, onSelectionChange }: Props) {
 	return (
-		<AriaTabs className={() => stylex.props(styles.root).className ?? ""}>
+		<AriaTabs
+			selectedKey={selectedKey}
+			onSelectionChange={onSelectionChange === undefined ? undefined : (key) => onSelectionChange(String(key))}
+			className={() => stylex.props(styles.root).className ?? ""}
+		>
 			<TabList aria-label={label} className={() => stylex.props(styles.list).className ?? ""}>
 				{tabs.map((tab) => (
 					<Tab