feat(frontend): 添加部门管理和系统配置页面

- 添加 department.ts 部门管理服务
- 添加 DepartmentManagementView.vue 部门管理页面
- 添加 SystemConfigView.vue 系统配置页面
- 更新路由配置添加新页面
- 更新 App.vue 添加系统菜单入口
- 前端编译验证通过

frontend/admin/src/services/department.ts

@@ -0,0 +1,87 @@
+/**
+ * 部门管理服务
+ */
+
+export interface Department {
+  id?: number
+  deptName: string
+  parentId?: number
+  deptCode?: string
+  leaderId?: number
+  sortOrder?: number
+  status: number
+  createdAt?: string
+}
+
+export interface ApiResponse<T> {
+  code: number
+  data: T
+  message?: string
+}
+
+class DepartmentService {
+  private baseUrl = '/api'
+
+  async getDepartments(): Promise<Department[]> {
+    const response = await fetch(`${this.baseUrl}/departments`, {
+      credentials: 'include'
+    })
+    const result = await response.json() as ApiResponse<Department[]>
+    if (result.code !== 200) {
+      throw new Error(result.message || '获取部门列表失败')
+    }
+    return result.data
+  }
+
+  async getDepartmentById(id: number): Promise<Department | null> {
+    const response = await fetch(`${this.baseUrl}/departments/${id}`, {
+      credentials: 'include'
+    })
+    const result = await response.json() as ApiResponse<Department>
+    if (result.code !== 200) {
+      return null
+    }
+    return result.data
+  }
+
+  async createDepartment(data: Department): Promise<number> {
+    const response = await fetch(`${this.baseUrl}/departments`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      credentials: 'include',
+      body: JSON.stringify(data)
+    })
+    const result = await response.json() as ApiResponse<number>
+    if (result.code !== 200) {
+      throw new Error(result.message || '创建部门失败')
+    }
+    return result.data
+  }
+
+  async updateDepartment(id: number, data: Department): Promise<void> {
+    const response = await fetch(`${this.baseUrl}/departments/${id}`, {
+      method: 'PUT',
+      headers: { 'Content-Type': 'application/json' },
+      credentials: 'include',
+      body: JSON.stringify(data)
+    })
+    const result = await response.json() as ApiResponse<void>
+    if (result.code !== 200) {
+      throw new Error(result.message || '更新部门失败')
+    }
+  }
+
+  async deleteDepartment(id: number): Promise<void> {
+    const response = await fetch(`${this.baseUrl}/departments/${id}`, {
+      method: 'DELETE',
+      credentials: 'include'
+    })
+    const result = await response.json() as ApiResponse<void>
+    if (result.code !== 200) {
+      throw new Error(result.message || '删除部门失败')
+    }
+  }
+}
+
+export const departmentService = new DepartmentService()
+export default departmentService