feat: add employee management, backend health check, and UI improvements

web/src/services/api.js

@@ -0,0 +1,39 @@
+const API_BASE = String(import.meta.env.VITE_API_BASE_URL || '/api/v1').replace(/\/$/, '')
+
+function buildUrl(path) {
+  if (!path.startsWith('/')) {
+    return `${API_BASE}/${path}`
+  }
+
+  return `${API_BASE}${path}`
+}
+
+export async function apiRequest(path, options = {}) {
+  let response
+
+  try {
+    response = await fetch(buildUrl(path), {
+      headers: {
+        'Content-Type': 'application/json',
+        ...(options.headers || {})
+      },
+      ...options
+    })
+  } catch {
+    throw new Error('无法连接后端员工服务，请确认 FastAPI 已启动。')
+  }
+
+  let payload = null
+
+  try {
+    payload = await response.json()
+  } catch {
+    payload = null
+  }
+
+  if (!response.ok) {
+    throw new Error(payload?.detail || '接口请求失败，请稍后重试。')
+  }
+
+  return payload
+}