docs: Update configuration examples, API documentation, and add a deployment guide.

config.example.json

@@ -1,23 +1,28 @@
 {
+  "_comment": "DS2API 配置文件示例 - 复制为 config.json 使用",
+  "_doc": "详细文档: https://github.com/CJackHwang/ds2api",
   "keys": [
     "your-api-key-1",
     "your-api-key-2"
   ],
   "accounts": [
     {
+      "_comment": "邮箱登录方式",
       "email": "example1@example.com",
       "password": "your-password-1",
       "token": ""
     },
     {
+      "_comment": "邮箱登录方式 - 账号2",
       "email": "example2@example.com",
       "password": "your-password-2",
       "token": ""
     },
     {
+      "_comment": "手机号登录方式（中国大陆）",
       "mobile": "12345678901",
       "password": "your-password-3",
       "token": ""
     }
   ]
-}
+}