refactor: fix all Low findings from FLAWS_REPORT audit

- Auth: TOTP params from config, JWT error logging, audit log failure
  logging, replaced_by_hash validation on token rotation
- Invoices: remove dead VAT code, consistent PDF permissions,
  WebP magic-byte detection, deduped exchange-rate fetches
- Orders/Offers: multipart limit from config, use paginated() helper,
  payment method from DB in PDF
- Projects: verify project exists before creating note
- Attendance: action_type enum validation, consistent local-time
  shift_date construction, holiday attendance in work fund,
  trips.view permission on last-km query
- Users: paginated() helper usage, remove duplicate dashboard keys,
  parallel currency conversion, single hashToken implementation
- Frontend: memoized customInput, reliable print onload, modal prop
  standardization (isOpen), ConfirmModal type icons, id===0 key
  fallback, Login useCallback, CompanySettings ConfirmModal,
  Attendance timeout cleanup, Dashboard memoization, beforeunload
  dirty-state warnings on Invoice/Offer/Order detail
- Schema: invoice_alert_log timestamp, config/env comment on
  Date.prototype.toJSON override
- Utils: exchange-rate inflight dedup

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

src/admin/components/ShiftFormModal.tsx

@@ -68,7 +68,7 @@ interface ProjectLogRowProps {
 
 export interface ShiftFormModalProps {
   mode: "create" | "edit";
-  show: boolean;
+  isOpen: boolean;
   onClose: () => void;
   onSubmit: () => void;
   form: ShiftFormData;
@@ -196,7 +196,7 @@ function ProjectLogRow({
 
 export default function ShiftFormModal({
   mode,
-  show,
+  isOpen,
   onClose,
   onSubmit,
   form,
@@ -208,7 +208,7 @@ export default function ShiftFormModal({
   onShiftDateChange,
   editingRecord,
 }: ShiftFormModalProps) {
-  useModalLock(show);
+  useModalLock(isOpen);
   const isCreate = mode === "create";
   const isWorkType = form.leave_type === "work";
 
@@ -240,7 +240,7 @@ export default function ShiftFormModal({
 
   return (
     <AnimatePresence>
-      {show && (
+      {isOpen && (
         <motion.div
           className="admin-modal-overlay"
           initial={{ opacity: 0 }}