Phase 6

Owner Administration is complete. Summary of this final stretch of work:

Seed data extended with an inactive staff member, a pending invitation, a redeemed-reward fixture, a service with no eligible staff, and a future-appointment fixture for conflict testing — all idempotent, verified against the dev DB.

Testing brought to 179 unit / 86 integration / 27 E2E tests, all passing together on a freshly seeded, disposable Postgres:

Unit tests for every new pure validator (business hours, categories/services, booking rules, loyalty config, staff creation).
Integration tests covering opening-hours conflicts, last-owner protection, staff deactivation/eligibility conflicts, loyalty redemption's atomic race-guard, and owner-vs-barber/business-isolation authorization — all against a real Postgres.
12 new Playwright owner journeys, which surfaced and fixed two genuine issues along the way: a cookie-clearing race condition in the sign-out-mid-test flow (a real, reproducible timing bug, not just a test artifact), and confirmation that seed fixtures upserted by deterministic ID go stale once "today" has moved on — now handled defensively.
Desktop responsiveness: converted the single-column Business Details, Booking Rules, and Loyalty Configuration forms to a genuine two-column layout at the lg: breakpoint (verified via measured element positions, not just screenshots), confirmed mobile stacking is unaffected.

Final verification: clean tsc, eslint, and next build, plus the full three-suite run against one fresh database as the authoritative pass.

src/app/(owner)/layout.tsx

@@ -3,6 +3,7 @@ import { auth } from "@/auth";
 import { StaffShell } from "@/components/navigation/staff-shell";
 import { hasPermission } from "@/lib/auth/permissions";
 import { Permission } from "@/generated/prisma/enums";
+import { OWNER_NAV_ITEMS } from "@/lib/navigation/staff-nav-items";
 
 /**
  * Owner is a permission on a staff account, not a separate account type
@@ -20,5 +21,9 @@ export default async function OwnerLayout({ children }: { children: React.ReactN
     redirect("/staff");
   }
 
-  return <StaffShell>{children}</StaffShell>;
+  return (
+    <StaffShell items={OWNER_NAV_ITEMS} footerLink={{ href: "/staff", label: "Barber Tools" }}>
+      {children}
+    </StaffShell>
+  );
 }