v1.8.0: warehouse module (16 commits), docházka mzda model, leave_type=holiday removal, api.ts race fix

Highlights:
- Warehouse module: receipts, issues, reservations, inventory, reports, dashboard,
  master data (categories, suppliers, locations), FIFO service, integration tests
- Docházka: mzda PDF counting model (Odpracováno / Vč. svátků / Přesčas / Svátek /
  So/Ne / Noc) with Czech weekday names and decimal hours
- AttendanceAdmin/AttendanceHistory KPI cards unified to mzda formula with
  fund bar colored by delta, badges for Práce/Dov/Nem/Sv/Nep
- Remove leave_type=holiday entirely (auto-computed from Czech public holidays)
- Allow multiple work shifts per day (overlap detection only)
- Pre-flight refresh in api.ts eliminates spurious 401s on fresh page loads
- Prisma: company_settings gets 6 nullable columns for warehouse numbering
  (PRI/VYD/INV prefixes, default patterns); migration seeds defaults

src/admin/lib/queries/mutations.ts

@@ -0,0 +1,113 @@
+import {
+  useMutation,
+  useQueryClient,
+  type UseMutationOptions,
+} from "@tanstack/react-query";
+import apiFetch from "../../utils/api";
+
+export interface ApiError extends Error {
+  status?: number;
+}
+
+export type HttpMethod = "POST" | "PUT" | "PATCH" | "DELETE";
+
+interface ApiResponseBody<T> {
+  success: boolean;
+  data?: T;
+  error?: string;
+  message?: string;
+}
+
+async function performMutation<TIn, TOut>(opts: {
+  url: string | ((input: TIn) => string);
+  method: HttpMethod | ((input: TIn) => HttpMethod);
+  body?: TIn;
+}): Promise<TOut> {
+  const url =
+    typeof opts.url === "function" ? opts.url(opts.body as TIn) : opts.url;
+  const method =
+    typeof opts.method === "function"
+      ? opts.method(opts.body as TIn)
+      : opts.method;
+  const response = await apiFetch(url, {
+    method,
+    headers:
+      opts.body !== undefined
+        ? { "Content-Type": "application/json" }
+        : undefined,
+    body: opts.body !== undefined ? JSON.stringify(opts.body) : undefined,
+  });
+
+  if (response.status === 401) {
+    const err: ApiError = new Error("Unauthorized");
+    err.status = 401;
+    throw err;
+  }
+
+  let result: ApiResponseBody<TOut>;
+  try {
+    result = (await response.json()) as ApiResponseBody<TOut>;
+  } catch {
+    throw new Error("Invalid JSON response");
+  }
+
+  if (!response.ok || !result.success) {
+    const err: ApiError = new Error(
+      result.error || `Request failed (${response.status})`,
+    );
+    err.status = response.status;
+    throw err;
+  }
+
+  return result.data as TOut;
+}
+
+export interface ApiMutationOptions<TIn, TOut> {
+  url: string | ((input: TIn) => string);
+  method: HttpMethod | ((input: TIn) => HttpMethod);
+  /** Query-key prefixes to invalidate on success. Broad per CLAUDE.md. */
+  invalidate?: readonly string[];
+}
+
+/**
+ * Hook that wraps `useMutation` with `apiFetch` and broad-invalidation.
+ *
+ * Usage:
+ *   const createCategory = useApiMutation<CategoryForm, WarehouseCategory>({
+ *     url: "/api/admin/warehouse/categories",
+ *     method: "POST",
+ *     invalidate: ["warehouse"],
+ *   });
+ *   createCategory.mutate(form, {
+ *     onSuccess: () => { ... },
+ *   });
+ *
+ * The returned `data` from a successful mutation is `TOut`. Errors are thrown
+ * as `ApiError` (with `.status` attached) so callers can branch on HTTP code.
+ */
+export function useApiMutation<TIn, TOut>(
+  opts: ApiMutationOptions<TIn, TOut> &
+    Omit<UseMutationOptions<TOut, ApiError, TIn>, "mutationFn">,
+) {
+  const { url, method, invalidate, onSuccess, ...rest } = opts;
+  const queryClient = useQueryClient();
+
+  return useMutation<TOut, ApiError, TIn, unknown>({
+    mutationFn: (input: TIn) =>
+      performMutation<TIn, TOut>({ url, method, body: input }),
+    ...rest,
+    onSuccess: (data, variables, onMutateResult, context) => {
+      if (invalidate) {
+        for (const key of invalidate) {
+          queryClient.invalidateQueries({ queryKey: [key] });
+        }
+      }
+      // Forward to user-provided onSuccess with the 4-arg signature expected by TanStack.
+      (
+        onSuccess as
+          | ((d: TOut, v: TIn, r: unknown, c: unknown) => void)
+          | undefined
+      )?.(data, variables, onMutateResult, context);
+    },
+  });
+}