fix: 2026-06-09 full-codebase audit hardening

Validation: shared NaN-guarded Zod coercion helpers in schemas/common.ts replace
the raw number|string transform idiom across every schema (the root-cause NaN bug
class); emailOrEmpty + lenient isoDateString/timeString.

Security: roles privilege-escalation closed; refresh-token family revocation on
reuse; TOTP uses config params; read endpoints permission-guarded; received-invoices
gross VAT on all paths; orders-pdf custom-items authz.

Concurrency: $queryRaw SELECT...FOR UPDATE locks in ascending-id order (warehouse
confirm/cancel, attendance lockUserRow); uniqueness checks moved into create
transactions (TOCTOU -> 409); deterministic id tiebreak on second-precision
timestamp ordering (plan resolveCell/resolveGrid, warehouse FIFO).

Frontend: Rules-of-Hooks fixed across ~14 pages + PlanCellModal; UTC-date persisted
fields; dashboard invalidation gaps; stale-closure confirm bugs.

Tooling/tests: ESLint flat config (react-hooks/rules-of-hooks = error) + Prettier;
tsconfig.test.json so tsc -b type-checks the tests; removed 3 dead deps; npm audit
fix (8 -> 3). Suite 195 -> 247 (happy-path auth, FIFO oldest-first, flakiness fixes),
isolated on app_test via .env.test with a hard-throw setup guard.

Gates: tsc 0 | build 0 | vitest 247/247 | eslint 0 errors.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/admin/pages/Invoices.tsx

@@ -10,7 +10,13 @@ import CircularProgress from "@mui/material/CircularProgress";
 import Forbidden from "../components/Forbidden";
 
 import apiFetch from "../utils/api";
-import { formatCurrency, formatDate, czechPlural } from "../utils/formatters";
+import {
+  formatCurrency,
+  formatDate,
+  czechPlural,
+  todayLocalStr,
+} from "../utils/formatters";
+import { normalizeDateStr } from "../utils/attendanceHelpers";
 import { usePaginatedQuery } from "../hooks/usePaginatedQuery";
 import useTableSort from "../hooks/useTableSort";
 import {
@@ -499,12 +505,14 @@ export default function Invoices() {
   };
 
   // Per-row overdue tint (replaces offers-expired-row).
+  // Compare as YYYY-MM-DD strings in LOCAL time (lexicographic === chronological)
+  // to avoid the UTC-vs-local off-by-one near midnight Prague.
   const rowSx = (inv: Invoice) => {
     const isOverdue =
       inv.status === "overdue" ||
       (inv.status === "issued" &&
-        inv.due_date &&
-        new Date(inv.due_date) < new Date(new Date().toDateString()));
+        !!inv.due_date &&
+        normalizeDateStr(inv.due_date) < todayLocalStr());
     if (isOverdue) {
       return {
         backgroundColor: "rgba(var(--mui-palette-warning-mainChannel) / 0.12)",