feat(T06): Mietkatalog frontend – equipment list, detail, search/filter, SSR

- composables/useApi.ts: base API client with runtimeConfig
- composables/useEquipment.ts: equipment API wrapper (list, detail, categories)
- components/EquipmentCard.vue: card with image/placeholder, badge, name, price, add-to-cart
- pages/mietkatalog.vue: SSR list with search, category chips, sort, pagination, skeleton, empty/error states
- pages/mietkatalog/[id].vue: SSR detail with specs table, related items, breadcrumb, add-to-cart
- nuxt.config.ts: runtimeConfig with apiBase
- 101 vitest tests passing (5 files)
- Build: 0 errors, 2.09 MB

frontend/composables/useEquipment.ts

@@ -0,0 +1,83 @@
+/**
+ * Equipment API composable.
+ * Wraps useApi to provide typed equipment list, detail, and categories endpoints.
+ */
+
+export interface EquipmentItem {
+  id: number;
+  rentman_id: string;
+  name: string;
+  number: string | null;
+  category: string | null;
+  description: string | null;
+  image_url: string | null;
+  rental_price: number | null;
+  available: boolean;
+}
+
+export interface EquipmentDetail {
+  id: number;
+  rentman_id: string;
+  name: string;
+  number: string | null;
+  category: string | null;
+  description: string | null;
+  specifications: Record<string, unknown> | null;
+  images: string[] | null;
+  rental_price: number | null;
+  brand: string | null;
+  available: boolean;
+}
+
+export interface PaginatedEquipment {
+  items: EquipmentItem[];
+  total: number;
+  page: number;
+  page_size: number;
+  total_pages: number;
+}
+
+export type SortOption = "name_asc" | "name_desc";
+
+export function useEquipment() {
+  const api = useApi();
+
+  /**
+   * Fetch paginated equipment list with search, category filter, and sort.
+   */
+  async function list(params: {
+    search?: string;
+    category?: string;
+    sort?: SortOption;
+    page?: number;
+    page_size?: number;
+  } = {}): Promise<PaginatedEquipment> {
+    return api.get<PaginatedEquipment>("/api/equipment", {
+      search: params.search || undefined,
+      category: params.category || undefined,
+      sort: params.sort || "name_asc",
+      page: params.page || 1,
+      page_size: params.page_size || 20,
+    });
+  }
+
+  /**
+   * Fetch a single equipment detail by ID.
+   */
+  async function detail(id: number | string): Promise<EquipmentDetail> {
+    return api.get<EquipmentDetail>(`/api/equipment/${id}`);
+  }
+
+  /**
+   * Fetch all available equipment categories.
+   */
+  async function categories(): Promise<string[]> {
+    return api.get<string[]>("/api/equipment/categories");
+  }
+
+  return {
+    list,
+    detail,
+    categories,
+  };
+}