📝 docs(authentication): add varible NEXTAUTH_URL (lobehub#1335)

Author: cy948

docs/self-hosting/advanced/authentication.mdx

@@ -53,6 +53,7 @@ When deploying LobeChat, you need to configure the following environment variabl
 | `AUTH0_CLIENT_SECRET` | Required | Client Secret of the Auth0 application |
 | `AUTH0_ISSUER` | Required | Domain of the Auth0 application, `https://example.auth0.com` |
 | `ACCESS_CODE` | Required | Add a password to access this service. You can set a sufficiently long random password to "disable" access code authorization. |
+| `NEXTAUTH_URL` | Optional | The URL is used to specify the callback address for the execution of OAuth authentication in Auth.js. It needs to be set only when the default address is incorrect. `https://example.com/api/auth` |
 
 You can refer to the related variable details at [Environment Variables](/en/self-hosting/environment-variable#auth0).
 

docs/self-hosting/advanced/authentication.zh-CN.mdx

@@ -54,6 +54,7 @@ http(s)://your-domain/api/auth/callback/auth0
 | `AUTH0_CLIENT_SECRET` | 必选 | Auth0 应用程序的 Client Secret |
 | `AUTH0_ISSUER` | 必选 | Auth0 应用程序的 Domain，`https://example.auth0.com` |
 | `ACCESS_CODE` | 必选 | 添加访问此服务的密码，你可以设置一个足够长的随机密码以 “禁用” 访问码授权 |
+| `NEXTAUTH_URL` | 可选 | 该URL用于指定 Auth.js 在执行 OAuth 验证时的回调地址，当默认生成的重定向地址发生不正确时才需要设置。`https://example.com/api/auth` |
 
 前往 [环境变量](/zh/self-hosting/environment-variable#auth0) 可查阅相关变量详情。