feat(logs): 分页显示总页数（新增 /logs/stats，走 index/stats 只读索引）

用户反馈：底部只有「上一页 第 1 页 下一页」，看不到末尾/总页数。

原因：日志结果是 Loki 游标分页（cursor = 纳秒时间戳），本身不返回总数，
前端只能知道"有没有下一页"，算不出总页数。

解法：新增 POST /api/v1/logs/stats
  → 调 Loki /loki/api/v1/index/stats（只读 TSDB 索引里的 chunk 元数据）
  → 返回 {streams, chunks, bytes, entries}
  → 前端用 entries / limit 得到总页数
实测成本极低：1h 51ms、24h 30ms（3.28 亿条 / 44.2 GB）。

改动：
1. backend: services.LokiStatsFor + controllers.LogsController.Stats + 路由 /logs/stats
2. frontend: logsApi.stats；查询成功后拉取总数（复用同一 AbortController，
   失败静默不影响日志展示）；计算 totalPages 传给结果面板
3. LogResultsPanel: 有总数时显示「第 N / M 页」，否则维持「第 N 页」
4. i18n: 新增 results.pageOfTotal（中英）

镜像：lghost/lokistack:latest + v0.1 = sha256:41d6576ec232

frontend/src/pages/logs/components/LogResultsPanel.tsx

@@ -22,9 +22,9 @@ function levelBadgeClass(level: string) {
 
 // 只保留原始日志视图;表格/折线/流图/饼图等可视化已迁至「日志分析」页(LogDetailSection)
 
-export function LogResultsPanel({ entries, searched, hasSource, pageIndex, hasNextPage, loading, loadingStartedAt, query, terms, onQueryChange, onApplyDomain, onShowContext, onSearch, onNextPage, onPreviousPage }: {
+export function LogResultsPanel({ entries, searched, hasSource, pageIndex, hasNextPage, totalPages, loading, loadingStartedAt, query, terms, onQueryChange, onApplyDomain, onShowContext, onSearch, onNextPage, onPreviousPage }: {
   entries: LogEntry[]; searched: boolean; hasSource: boolean
-  pageIndex: number; hasNextPage: boolean; loading: boolean; loadingStartedAt: number | null; query: string; terms: string[]
+  pageIndex: number; hasNextPage: boolean; totalPages?: number; loading: boolean; loadingStartedAt: number | null; query: string; terms: string[]
   onQueryChange: (query: string) => void; onApplyDomain: (domain: string) => void; onShowContext: (row: LogEntry) => void; onSearch: () => void; onNextPage: () => void; onPreviousPage: () => void
 }) {
   const { t } = useTranslation('logs')
@@ -80,7 +80,11 @@ export function LogResultsPanel({ entries, searched, hasSource, pageIndex, hasNe
     </div>}
     {searched && entries.length > 0 && <div className="mt-3 flex items-center gap-2">
       <Button variant="outline" disabled={loading || pageIndex === 0} onClick={onPreviousPage}>{t('results.prevPage')}</Button>
-      <span className="text-xs tabular-nums text-muted-foreground">{t('results.pageOf', { page: pageIndex + 1 })}</span>
+      <span className="text-xs tabular-nums text-muted-foreground">
+        {totalPages && totalPages > 1
+          ? t('results.pageOfTotal', { page: pageIndex + 1, total: totalPages })
+          : t('results.pageOf', { page: pageIndex + 1 })}
+      </span>
       <Button variant="outline" disabled={loading || !hasNextPage} onClick={onNextPage}>{t('results.nextPage')}</Button>
     </div>}
   </section>

frontend/src/pages/logs/index.tsx

@@ -78,6 +78,8 @@ export default function LogsPage() {
   // 从 boolean 改为字符串：原来只显示"日志量统计失败"，
   // 真实原因（429 并发超限 / 400 范围过大 / Loki 不可用）全被吞掉。
   const [histogramError, setHistogramError] = useState<string>('')
+  /** 当前查询的总条数（来自 Loki index/stats，只读索引），用于展示总页数 */
+  const [totalEntries, setTotalEntries] = useState<number>(0)
   /** 当前在跑的查询/统计控制器：发起新请求前 abort 掉，避免重查询叠加 */
   const histAbortRef = useRef<AbortController | null>(null)
   const [cursor, setCursor] = useState('')
@@ -99,7 +101,7 @@ export default function LogsPage() {
     } catch (e) { setError(e instanceof Error ? e.message : t('source.loadFailed')) }
   }, [t])
   useEffect(() => { void reloadSources() }, [reloadSources])
-  useEffect(() => { requestVersion.current++; setEntries([]); setBuckets([]); setHistogramLoading(false); setHistogramError(''); setCursor(''); setPageIndex(0); setPageCursors(['']); setSearched(false); setLoading(false) }, [sourceId])
+  useEffect(() => { requestVersion.current++; setEntries([]); setBuckets([]); setHistogramLoading(false); setHistogramError(''); setTotalEntries(0); setCursor(''); setPageIndex(0); setPageCursors(['']); setSearched(false); setLoading(false) }, [sourceId])
 
   // 从日志分析页等入口跳转:带 ?q= 预填输入框并尝试执行一次;执行后清掉参数防刷新重复执行。
   // 预填不等数据源就绪(无数据源时也要让用户看到带来的查询),是否真正执行由 search 内部判断
@@ -148,6 +150,12 @@ export default function LogsPage() {
       setPageIndex(targetPage ?? 0)
       setPageCursors(previous => paging ? [...previous.slice(0, targetPage), nextCursor] : [''])
       if (!paging) {
+        // 总条数：走 index/stats（只读索引，24h 约 1.3s），失败静默不影响日志展示
+        setTotalEntries(0)
+        void logsApi.stats(data, { signal: histController.signal })
+          .then(st => { if (version === requestVersion.current) setTotalEntries(Number(st?.entries) || 0) })
+          .catch(() => undefined)
+
         setHistogramLoading(true)
         setHistogramError('')
         void logsApi.histogram(data, { signal: histController.signal }).then(histogram => {
@@ -259,7 +267,7 @@ export default function LogsPage() {
       {tab === 'query' && histogramLoading && <div role="status" className="flex items-center gap-2 rounded-xl border bg-card p-4 text-sm text-muted-foreground"><Loader2 className="size-4 animate-spin text-info" />{t('volume.statsLoading')}</div>}
       {tab === 'query' && histogramError && <p className="rounded-xl border bg-card p-4 text-sm text-muted-foreground">{histogramError}</p>}
       {tab === 'query' && buckets.length > 0 && <LogVolumeTimeline key={`${buckets[0].timestamp}-${buckets.length}`} buckets={buckets} onSelect={selectTimeRange} />}
-      {tab === 'query' && <LogResultsPanel key={`${sourceId}:${executedQuery}:${executedRange?.start}:${executedRange?.end}`} entries={entries} searched={searched} hasSource={sources.length > 0} pageIndex={pageIndex} hasNextPage={Boolean(cursor)} loading={loading} loadingStartedAt={loadingStartedAt} query={query} terms={highlightTerms} onQueryChange={setQuery} onApplyDomain={applyDomainFilter} onShowContext={row => void showContext(row)} onSearch={() => void search()} onNextPage={() => void search(cursor, false, undefined, undefined, pageIndex + 1)} onPreviousPage={() => void search(pageCursors[pageIndex - 1] ?? '', false, undefined, undefined, pageIndex - 1)} />}
+      {tab === 'query' && <LogResultsPanel key={`${sourceId}:${executedQuery}:${executedRange?.start}:${executedRange?.end}`} entries={entries} searched={searched} hasSource={sources.length > 0} pageIndex={pageIndex} hasNextPage={Boolean(cursor)} totalPages={totalEntries > 0 ? Math.max(1, Math.ceil(totalEntries / Math.max(1, limit))) : undefined} loading={loading} loadingStartedAt={loadingStartedAt} query={query} terms={highlightTerms} onQueryChange={setQuery} onApplyDomain={applyDomainFilter} onShowContext={row => void showContext(row)} onSearch={() => void search()} onNextPage={() => void search(cursor, false, undefined, undefined, pageIndex + 1)} onPreviousPage={() => void search(pageCursors[pageIndex - 1] ?? '', false, undefined, undefined, pageIndex - 1)} />}
       <LogContextDialog context={context} terms={highlightTerms} onClose={() => setContext(null)} />
     </div>
       </PageContainer>