feat(toplist): 新增 npm Top200 周榜缓存功能

- db.js: 新增 top_list 表 + replaceTopList/getTopListRows/getTopListCount
- npm-toplist.js: 核心模块（Search+Downloads 复核+缓存比对+经私服拉取）
- server.js: /api/toplist* 端点 + scheduleWeeklyTopList（周一 00:00 定时抓榜）
- 前端: TopListView 页面、路由、顶/底栏菜单、store/api 扩展

实现: 22 关键词 Search 粗排 350 → Downloads 复核截 200 → 与 rawCache 三态比对（待拉取/需更新/已就绪）→ 一键拉取待缓存/需更新包
复用 sync-latest 的 triggerVerdaccio 落盘机制，限流 1.5s 间隔 + 429 指数退避

backend/server.js

@@ -19,7 +19,7 @@ import { randomUUID } from 'node:crypto'
 import { fileURLToPath } from 'node:url'
 import {
   getSetting, setSetting, getIgnored, getIgnoredRows, addIgnored, removeIgnored,
-  addLog, getLogs,
+  addLog, getLogs, nowIso,
 } from './db.js'
 import {
   resolveStorageDir, isValidStorage, validateStorage, scanStorage, scanStorageAsync,
@@ -28,6 +28,7 @@ import {
 import { cleanPackage, deleteSingleVersion } from './clean.js'
 import semverCompare from './semver.js'
 import { syncState, runSyncLatest } from './sync-latest.js'
+import { toplistState, runTopListFetch, runTopListPull, getTopList } from './npm-toplist.js'
 
 const __dirname = path.dirname(fileURLToPath(import.meta.url))
 const app = express()
@@ -481,6 +482,78 @@ app.get('/api/sync/progress', (req, res) => {
   })
 })
 
+// —— API：Top200 榜单 ——
+app.get('/api/toplist', (req, res) => {
+  const { filter } = req.query
+  const data = getTopList(getRawPackages)
+  if (filter === 'missing') {
+    data.list = data.list.filter(e => !e.cached)
+  } else if (filter === 'outdated') {
+    data.list = data.list.filter(e => e.cached && !e.latestCached)
+  } else if (filter === 'ready') {
+    data.list = data.list.filter(e => e.cached && e.latestCached)
+  }
+  res.json(data)
+})
+
+app.get('/api/toplist/progress', (req, res) => {
+  res.json(toplistState)
+})
+
+app.post('/api/toplist/fetch', (req, res) => {
+  if (!toplistState.running) {
+    runTopListFetch({
+      addLog,
+      getRawPackages,
+      invalidateScan,
+      setSetting,
+    })
+  }
+  res.json({
+    ok: true,
+    running: toplistState.running,
+    phase: toplistState.phase,
+    startedAt: toplistState.startedAt,
+  })
+})
+
+app.post('/api/toplist/pull', (req, res) => {
+  if (isDemoMode()) {
+    return res.json({ ok: true, demo: true, running: false, message: '演示模式：未配置 Verdaccio 缓存目录，不支持拉取' })
+  }
+  if (!toplistState.pullRunning) {
+    runTopListPull({
+      addLog,
+      getRawPackages,
+      invalidateScan,
+    })
+  }
+  res.json({
+    ok: true,
+    demo: false,
+    running: toplistState.pullRunning,
+    total: toplistState.pullTotal,
+    startedAt: toplistState.pullStartedAt,
+  })
+})
+
+app.get('/api/toplist/pull/progress', (req, res) => {
+  res.json({
+    running: toplistState.pullRunning,
+    done: toplistState.pullDone,
+    total: toplistState.pullTotal,
+    processed: toplistState.pullProcessed,
+    success: toplistState.pullSuccess,
+    skipped: toplistState.pullSkipped,
+    failed: toplistState.pullFailed,
+    failedList: toplistState.pullFailedList,
+    current: toplistState.pullCurrent,
+    error: toplistState.pullError,
+    startedAt: toplistState.pullStartedAt,
+    finishedAt: toplistState.pullFinishedAt,
+  })
+})
+
 // —— API：清理 ——
 app.post('/api/clean', (req, res) => {
   const { pkgName, keep } = req.body || {}
@@ -593,6 +666,7 @@ app.listen(PORT, () => {
   if (mode === 'storage') console.log(`[verdaccio-manager] storage: ${storage}`)
   else console.log('[verdaccio-manager] 未配置 VERDACCIO_STORAGE，运行于演示模式（设置 VCM_DEMO=0 + 真实目录可关闭）')
   scheduleDailyScan()
+  scheduleWeeklyTopList()
 })
 
 // 清理登录限速表：超过窗口 + 锁定期的记录不再保留（防 Map 无限增长）
@@ -633,6 +707,27 @@ function scheduleDailyScan() {
   }, wait)
 }
 
+// —— 每周一 00:00（服务器本地时区）自动抓取 Top200 榜单 ——
+//   与每日扫描（03:00）错峰，避免并发冲突
+function scheduleWeeklyTopList() {
+  const now = new Date()
+  const next = new Date(now)
+  next.setHours(0, 0, 0, 0)
+  const dow = next.getDay() // 0=Sun, 1=Mon
+  let daysUntilMonday = (1 - dow + 7) % 7
+  if (daysUntilMonday === 0 && now.getTime() > next.getTime()) daysUntilMonday = 7
+  next.setDate(next.getDate() + daysUntilMonday)
+  setSetting('toplist_next_run', nowIso(next))
+  setTimeout(async () => {
+    try {
+      await runTopListFetch({ addLog, getRawPackages, invalidateScan, setSetting })
+    } catch (e) {
+      console.error('[toplist] 定时抓榜失败:', e.message)
+    }
+    scheduleWeeklyTopList()
+  }, next.getTime() - now.getTime())
+}
+
 function clampInt(v, min, max) {
   const n = Number(v)
   if (Number.isNaN(n)) return min