feat: 完成P6-P8前端能力闭环（V3,D2,D3,B3）

client/src/api/dashboard.ts

@@ -0,0 +1,60 @@
+import { apiRequestData } from "./http";
+
+export type DashboardQuery = {
+  dateFrom?: string;
+  dateTo?: string;
+  departmentId?: string;
+  limit?: number;
+};
+
+function toQueryString(query: DashboardQuery = {}) {
+  const params = new URLSearchParams();
+  if (query.dateFrom) params.set("dateFrom", query.dateFrom);
+  if (query.dateTo) params.set("dateTo", query.dateTo);
+  if (query.departmentId) params.set("departmentId", query.departmentId);
+  if (query.limit != null) params.set("limit", String(query.limit));
+  const encoded = params.toString();
+  return encoded ? `?${encoded}` : "";
+}
+
+export type DashboardExpenseOverview = {
+  totalCount: number;
+  totalAmount: string;
+  paidCount: number;
+  paidAmount: string;
+  reviewingCount: number;
+};
+
+export type DashboardTrendPoint = {
+  date: string;
+  amount: string;
+  count: number;
+};
+
+export type DashboardTopCategory = {
+  code: string;
+  name: string;
+  amount: string;
+  count: number;
+};
+
+export type DashboardApprovalEfficiency = {
+  approvedCount: number;
+  averageHours: number;
+};
+
+export async function fetchDashboardOverview(query: DashboardQuery = {}) {
+  return apiRequestData<DashboardExpenseOverview>(`/api/dashboard/expense-overview${toQueryString(query)}`);
+}
+
+export async function fetchDashboardTrends(query: DashboardQuery = {}) {
+  return apiRequestData<{ points: DashboardTrendPoint[] }>(`/api/dashboard/trends${toQueryString(query)}`);
+}
+
+export async function fetchDashboardTopCategories(query: DashboardQuery = {}) {
+  return apiRequestData<{ items: DashboardTopCategory[] }>(`/api/dashboard/top-categories${toQueryString(query)}`);
+}
+
+export async function fetchDashboardApprovalEfficiency(query: DashboardQuery = {}) {
+  return apiRequestData<DashboardApprovalEfficiency>(`/api/dashboard/approval-efficiency${toQueryString(query)}`);
+}