v1.6.5: fix attendance unique constraint, schema sync, seed script

- Change attendance idx_attendance_user_date from unique to index (allow multiple shifts per day)
- Reset migrations to single baseline init migration
- Add seed script with admin user (admin/admin)
- Update CLAUDE.md with migration workflow documentation
- Various frontend fixes (queries, pages, hooks)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/admin/pages/LeaveRequests.tsx

@@ -9,7 +9,7 @@ import LeaveRequestsFixture from "../fixtures/LeaveRequestsFixture";
 import { formatDate, formatDatetime } from "../utils/attendanceHelpers";
 import apiFetch from "../utils/api";
 import ConfirmModal from "../components/ConfirmModal";
-import { leaveRequestsOptions } from "../lib/queries/leave";
+import { leaveRequestsOptions, type LeaveRequest } from "../lib/queries/leave";
 
 const API_BASE = "/api/admin";
 
@@ -39,26 +39,13 @@ const leaveTypeClasses: Record<string, string> = {
   unpaid: "badge-unpaid",
 };
 
-interface LeaveRequest {
-  id: number;
-  leave_type: string;
-  date_from: string;
-  date_to: string;
-  total_days: number;
-  total_hours: number;
-  status: string;
-  notes?: string;
-  reviewer_note?: string;
-  created_at: string;
-}
-
 export default function LeaveRequests() {
   const alert = useAlert();
   const { hasPermission } = useAuth();
   const queryClient = useQueryClient();
   const { data: requests = [], isPending } = useQuery(
     leaveRequestsOptions(true),
-  ) as { data: LeaveRequest[]; isPending: boolean };
+  );
   const [cancelModal, setCancelModal] = useState<{
     open: boolean;
     id: number | null;
@@ -82,6 +69,8 @@ export default function LeaveRequests() {
       if (result.success) {
         setCancelModal({ open: false, id: null });
         queryClient.invalidateQueries({ queryKey: ["leave-requests"] });
+        queryClient.invalidateQueries({ queryKey: ["leave"] });
+        queryClient.invalidateQueries({ queryKey: ["attendance"] });
         alert.success(result.message);
       } else {
         alert.error(result.error);