[FEATURE] Support `enum` and `enumDescriptions` on Preference Settings View

[erha19]

如果你的需求与问题相关，请在下面描述一下（Is your feature request related to a problem? Please describe.）

configuration 贡献点声明如下：

{
   "contributes": {
     "configuration": {
       "magicCode.sdk.channel": {
          "type": "number",
          "default": 1,
          "enum": [
            1,
            2,
            3,
            4
          ],
          "enumDescriptions": [
            "稳定版本(#1 Stable)",
            "灰度版本(#2 Beta)",
            "开发版本(#3 Dev)",
            "尝鲜版本(#4 Canary)"
          ],
          "description": "Select from which channel to download sdk updates",
          "scope": "application"
        }
     }
   }
}

描述你预期的功能表现（Describe the solution you'd like）

设置面板响应位置应该展示为数组下拉选项，同时支持 description 展示

补充信息（Additional context）

初步定位 configuration 的贡献点是有存入数据结构的 configurationDefaults.ts

需要针对视图展示做一下额外处理，视图处理逻辑见 preferenceItem.view.tsx#L38，展示还没时间修复，有兴趣的同学可以着手修复一下

[erha19]

设置 enumDescriptions 情况下：

{
  "contributes": {
    "configuration": {
      "magicCode.sdk.osOverride": {
        "type": "string",
        "default": "",
        "enum": [
          "",
          "windows",
          "macos",
          "linux"
        ],
        "enumDescriptions": [
          "(Current OS)",
          "Windows",
          "Mac OS",
          "Linux"
        ],
        "description": "Select from which os type, the sdk artifacts will be downloaded",
        "scope": "application"
      },
    }
  }
}

选择后应该展示不同选项的描述信息：

[sinoon]

#382