Add authentication features for admin access

- Introduce a new `auth` module with login, logout, and user verification endpoints for a single admin user.
- Update backend routes to require admin authentication for sensitive operations, enhancing security.
- Modify frontend components to include an authentication provider and gate, ensuring only authorized users can access the application.
- Implement a login page for admin access, improving user experience and security management.
- Update API request handling to redirect unauthorized users to the login page, ensuring proper access control.

frontend/src/lib/api.ts

@@ -12,8 +12,16 @@ export type ModelType = "LLM" | "ASR" | "TTS" | "Realtime" | "Embedding" | "Agen
 async function request<T>(path: string, init?: RequestInit): Promise<T> {
   const res = await fetch(`${API_BASE}${path}`, {
     headers: { "Content-Type": "application/json" },
+    credentials: "include",
     ...init,
   });
+  if (
+    res.status === 401 &&
+    typeof window !== "undefined" &&
+    !path.startsWith("/api/auth/")
+  ) {
+    window.location.href = "/login";
+  }
   if (!res.ok) {
     let detail = `请求失败 (${res.status})`;
     try {
@@ -29,6 +37,25 @@ async function request<T>(path: string, init?: RequestInit): Promise<T> {
   return (text ? JSON.parse(text) : undefined) as T;
 }
 
+export type AdminUser = {
+  username: string;
+  displayName: string;
+  role: "super_admin";
+};
+
+export const authApi = {
+  login: (body: { username: string; password: string }) =>
+    request<AdminUser>("/api/auth/login", {
+      method: "POST",
+      body: JSON.stringify(body),
+    }),
+  logout: () =>
+    request<{ ok: boolean }>("/api/auth/logout", {
+      method: "POST",
+    }),
+  me: () => request<AdminUser>("/api/auth/me"),
+};
+
 // ---------- 接口定义驱动的模型注册表 ----------
 export type InterfaceField = {
   key: string;