refactor: 架构整固——分层单向化、全量 TypeScript、直接运行

- 移除 bd/mg 两平台及磁盘残留产物；清理 api-test 死脚本、musicSdk/message+options 死模块、infSign vendor
- musicSdk/ 改名 sdk/；src/common、src/auth、src/apis 整体移入 sdk/，依赖方向定为 src → sdk 严格单向
- src/ 手写 JS 全量转 .ts，删除 JS 类型垫片 modules.d.ts；源码 import 统一 .ts 后缀
- Node 原生类型剥离直接运行 .ts（engines >=22.18），取消 tsc 发射产物，tsc 仅类型检查（pnpm typecheck）
- 删除 kwdes 备用实现与 src/index.ts 转发垫片；测试移至 test/smoke-test.ts
- common/request.ts 补显式导出类型；修复 set-cookie 单值形态、ApiError 类字段等隐患

验证：tsc 零错误，smoke-test 41/41

sdk/kg/hotSearch.ts

@@ -0,0 +1,34 @@
+import { httpFetch } from '../request.ts'
+import { decodeName } from '../index.ts'
+import type { HttpRequestObject } from '../types.ts'
+
+export default {
+  _requestObj: null as HttpRequestObject | null,
+  async getList(retryNum = 0) {
+    if (this._requestObj) this._requestObj.cancelHttp()
+    if (retryNum > 2) return Promise.reject(new Error('try max num'))
+
+    const _requestObj = httpFetch('http://gateway.kugou.com/api/v3/search/hot_tab?signature=ee44edb9d7155821412d220bcaf509dd&appid=1005&clientver=10026&plat=0', {
+      method: 'get',
+      headers: {
+        dfid: '1ssiv93oVqMp27cirf2CvoF1',
+        mid: '156798703528610303473757548878786007104',
+        clienttime: '1584257267',
+        'x-router': 'msearch.kugou.com',
+        'user-agent': 'Android9-AndroidPhone-10020-130-0-searchrecommendprotocol-wifi',
+        'kg-rc': '1',
+      },
+    })
+    const { body, statusCode } = await _requestObj.promise
+    if (statusCode != 200 || body.errcode !== 0) throw new Error('获取热搜词失败')
+    // console.log(body, statusCode)
+    return { source: 'kg', list: this.filterList(body.data.list) }
+  },
+  filterList(rawList) {
+    const list: string[] = []
+    rawList.forEach(item => {
+      item.keywords.map(k => list.push(decodeName(k.keyword)))
+    })
+    return list
+  },
+}