main: 用户管理和会话功能初始实现

- 添加用户管理功能的测试，包括创建、更新、停用、激活用户及用户登录 JWT 测试
- 提供用户管理相关的请求验证类与控制器
- 引入 CORS 配置信息，支持跨域请求
- 添加数据库播种器以便创建根用户
- 配置 API 默认使用 JWT 认证
- 添加聊天会话和消息的模型、迁移文件及关联功能

app/Http/Controllers/AuthController.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace App\Http\Controllers;
+
+use App\Http\Requests\LoginRequest;
+use App\Models\User;
+use Illuminate\Http\JsonResponse;
+use Illuminate\Support\Facades\Hash;
+
+class AuthController extends Controller
+{
+    public function login(LoginRequest $request): JsonResponse
+    {
+        $credentials = $request->validated();
+
+        $user = User::whereEmail($credentials['email'])->first();
+
+        if (! $user || ! Hash::check($credentials['password'], $user->password)) {
+            return response()->json(['message' => '凭证无效'], 401);
+        }
+
+        if (! $user->is_active) {
+            return response()->json(['message' => '用户已停用'], 403);
+        }
+
+        $token = auth('api')->login($user);
+
+        return response()->json([
+            'token' => $token,
+            'token_type' => 'bearer',
+            'expires_in' => auth('api')->factory()->getTTL() * 60,
+            'user' => [
+                'id' => $user->id,
+                'name' => $user->name,
+                'email' => $user->email,
+                'is_active' => $user->is_active,
+            ],
+        ]);
+    }
+}