feat(sdk): 新增咪咕/千千/JOOX/哔哩哔哩/5sing/Apple Music 六平台

平台注册表由 9 个扩到 15 个，同时补齐 sdk/types.ts 的类型与
OpenAPI 文档里的能力位声明。

- migu：命中 Z3D/I3D 加密候选时不返回直链，改由服务端解密代理出流，
  SDK 侧只负责登记票据，避免客户端拿到无法播放的密文
- apple：只提供 preview 试听片段（完整曲为 DRM），标 noAggregate
  排除在跨平台精确匹配之外，防止用它顶掉其它平台的可播结果
- 其余平台按既有 PlatformModule 约定实现搜索/专辑/歌单/歌词

为什么合并成一次提交：六平台共用同一份注册表与能力位声明，
拆开会产生互相引用、单独无法通过类型检查的中间态。

sdk/apple/playlist.ts

@@ -0,0 +1,165 @@
+// Apple Music 歌单（上游 apple.go 的 SearchPlaylist / ParsePlaylist / GetPlaylistSongs /
+// GetPlaylistCategories / GetCategoryPlaylists 与 applePlaylistToPlaylist 映射）
+// 详情：amp-api /v1/catalog/<sf>/playlists/<id>?limit[tracks]=300&extend=extendedAssetUrls
+//   曲目超过一页时沿 relationships.tracks.next 全量拉取（上游 fetchAllTrackResources，带 20 页上限防死循环）。
+// 分类：上游使用写死的 Apple Music genre curator 列表（appleCuratorCategories），
+//   GetCategoryPlaylists 固定 storefront=cn + l=zh-Hans-CN（curator id 取自 cn 区）。
+// 链接：extractAppleID(link, 'playlist')，支持 pl.* 裸 id 与 /us/playlist/<slug>/pl.* 链接。
+import {
+  appleAmpGet,
+  applePlaylistToPlaylist,
+  appleSongFromCatalog,
+  extractAppleID,
+  fetchAllTrackResources,
+  getAppleConfig,
+} from './util.ts'
+
+export { searchPlaylist } from './musicSearch.ts'
+
+import { searchPlaylist } from './musicSearch.ts'
+
+/** 上游 appleCuratorCategories（从公开搜索落地页提取的 Apple Music genre curators） */
+export const appleCuratorCategories: Array<{ id: string, name: string }> = [
+  { id: '1526756058', name: '热门' },
+  { id: '1479949880', name: 'C-Pop' },
+  { id: '1019400042', name: '国语流行' },
+  { id: '1019398918', name: '粤语流行' },
+  { id: '1019399540', name: '国际流行' },
+  { id: '1019399551', name: 'K-Pop' },
+  { id: '1019399547', name: 'J-Pop' },
+  { id: '989061415', name: '嘻哈/说唱' },
+  { id: '1019400044', name: 'R&B' },
+  { id: '1019400046', name: '摇滚' },
+  { id: '1019397973', name: '另类音乐' },
+  { id: '976439535', name: '舞曲' },
+  { id: '976439536', name: '电子' },
+  { id: '976439541', name: '独立音乐' },
+  { id: '1019399549', name: '爵士乐' },
+  { id: '1019398924', name: '古典音乐' },
+  { id: '976439528', name: '蓝调' },
+  { id: '976439534', name: '乡村音乐' },
+  { id: '1531542847', name: '拉丁音乐' },
+  { id: '988656348', name: '非洲音乐' },
+  { id: '976439543', name: '金属乐' },
+  { id: '976439550', name: '朋克乐' },
+  { id: '1019400049', name: '不插电' },
+  { id: '1231181168', name: '影视原声' },
+  { id: '1441811365', name: 'DJ 混音精选' },
+  { id: '1532467784', name: '瞩目之星' },
+  { id: '1554938339', name: '年代之声' },
+  { id: '1564180390', name: '空间音频' },
+  { id: '989010186', name: '亲子' },
+]
+
+/** 上游 GetPlaylistCategories：静态返回 Apple Music genre curators */
+export const getCategories = async() => ({
+  source: 'apple' as const,
+  list: appleCuratorCategories.map(item => ({ id: item.id, name: item.name, group: 'Apple Music 分类', source: 'apple' as const })),
+})
+
+/** 上游 GetCategoryPlaylists：按 curator 分类取歌单（cn storefront，单请求上限 25，循环补齐） */
+export const getCategoryPlaylists = async(categoryID: string, page = 1, limit = 20) => {
+  const categoryId = String(categoryID ?? '').trim()
+  if (!categoryId) throw new Error('apple 分类 id 不能为空')
+  const p = Math.max(1, Number(page) || 1)
+  const l = Math.min(Math.max(1, Number(limit) || 20), 300)
+  const apiMax = 25
+  let offset = (p - 1) * l
+  const all: any[] = []
+
+  while (all.length < l) {
+    const batchSize = Math.min(apiMax, l - all.length)
+    let body: any
+    try {
+      body = await appleAmpGet(`/v1/catalog/cn/apple-curators/${categoryId}/playlists`, {
+        limit: batchSize,
+        offset,
+        l: 'zh-Hans-CN',
+      })
+    } catch (err) {
+      if (all.length > 0) break // 上游：已有数据时返回已取部分
+      throw err
+    }
+    const data = body?.data ?? []
+    all.push(...data.map((item: any) => applePlaylistToPlaylist(item)))
+    // 没有更多数据或没有下一页
+    if (data.length < batchSize || !body?.next) break
+    offset += data.length
+  }
+
+  return {
+    source: 'apple' as const,
+    list: all.slice(0, l),
+    page: p,
+    limit: l,
+    total: all.length,
+  }
+}
+
+/** 歌单详情（全量曲目后按 page/limit 切片） */
+export const getPlaylistDetail = async(rawId: string, page = 1, limit = 100) => {
+  const playlistId = extractAppleID(String(rawId ?? ''), 'playlist')
+  if (!playlistId) throw new Error(`invalid apple music playlist id/link: ${rawId}`)
+
+  const cfg = getAppleConfig()
+  const body: any = await appleAmpGet(`/v1/catalog/${cfg.storefront}/playlists/${playlistId}`, {
+    'limit[tracks]': 300,
+    extend: 'extendedAssetUrls',
+  })
+  const item = (body?.data ?? [])[0]
+  if (!item) throw new Error(`apple playlist not found: ${playlistId}`)
+
+  const tracks = await fetchAllTrackResources(item?.relationships?.tracks)
+  const songs = tracks.map((track: any) => appleSongFromCatalog(track))
+
+  const p = Math.max(1, Number(page) || 1)
+  const l = Math.max(1, Number(limit) || 100)
+  const summary = applePlaylistToPlaylist(item)
+  if (!summary.trackCount || songs.length > summary.trackCount) summary.trackCount = songs.length
+
+  return {
+    source: 'apple' as const,
+    info: {
+      id: playlistId,
+      name: summary.name,
+      img: summary.cover,
+      desc: summary.description,
+      author: summary.creator,
+      link: summary.link,
+      trackCount: summary.trackCount,
+    },
+    list: songs.slice((p - 1) * l, (p - 1) * l + l),
+    page: p,
+    limit: l,
+    total: songs.length,
+  }
+}
+
+/** 上游 GetPlaylistSongs：只返回曲目数组 */
+export const getPlaylistSongs = async(id: string): Promise<any[]> => {
+  const { list } = await getPlaylistDetail(id, 1, 100000)
+  return list
+}
+
+/** 上游 ParsePlaylist：歌单链接 → 详情（曲目全量，不分页） */
+export const parsePlaylistLink = async(link: string) => {
+  const detail = await getPlaylistDetail(link, 1, 100000)
+  return {
+    source: 'apple' as const,
+    id: detail.info.id,
+    info: detail.info,
+    list: detail.list,
+    page: 1,
+    limit: Math.max(detail.total, 1),
+    total: detail.total,
+  }
+}
+
+export default {
+  searchPlaylist,
+  getPlaylistDetail,
+  getPlaylistSongs,
+  getCategories,
+  getCategoryPlaylists,
+  parsePlaylistLink,
+}