chore(per-instance-hook-scoping): archive verified+synced change

Move to openspec/changes/archive/2026-07-09-per-instance-hook-scoping/
(R100 renames preserved). 9 artifacts. Canonical openspec/specs/
service-instance-scoping/ remains. Resolves multi-instance wrong-data bug
(hooks now scope by instance.id; instance switcher re-scopes).
Carry-overs: fetchBackupDashboard untouched (design decision 5); subquery
scoping for runs/alerts (schema asymmetry).

frontend/src/pages/service-tabs/AlertsTab.tsx

@@ -110,7 +110,9 @@ export function AlertsTab({ instance }: { instance: ServiceInstance }) {
 		isLoading: alertsLoading,
 		error: alertsError,
 	} = useAlertmanagerAlerts(instance.id);
-	const { data: status, isLoading: statusLoading } = useAlertmanagerStatus(instance.id);
+	const { data: status, isLoading: statusLoading } = useAlertmanagerStatus(
+		instance.id,
+	);
 
 	const statusDetail = status?.up
 		? status.version

frontend/src/pages/service-tabs/__tests__/AlertsTab.test.tsx

@@ -58,12 +58,12 @@ vi.mock("../../../hooks/useObservability", () => ({
 describe("AlertsTab", () => {
 	it("passes instance.id to scoped hooks", () => {
 		render(<AlertsTab instance={instance} />);
-		expect(vi.mocked(useObservability.useAlertmanagerAlerts)).toHaveBeenCalledWith(
-			"am-1",
-		);
-		expect(vi.mocked(useObservability.useAlertmanagerStatus)).toHaveBeenCalledWith(
-			"am-1",
-		);
+		expect(
+			vi.mocked(useObservability.useAlertmanagerAlerts),
+		).toHaveBeenCalledWith("am-1");
+		expect(
+			vi.mocked(useObservability.useAlertmanagerStatus),
+		).toHaveBeenCalledWith("am-1");
 	});
 
 	it("renders the alert count and alert names", () => {