fix(P2): no_data 结构化、权重校验、鉴权与前端竞态

P2-1 no_data 门控依赖文案子串(脆弱):
- context_builder 新增 SliceResult(text/has_data/n_records),
  5 个切片函数改为显式声明 has_data
- base._slice_has_data() 优先取结构化结果,str 返回仍走文案回退
  (兼容既有测试 mock 与自定义切片)
- build_context 的 has_stats/has_injuries 直接取切片声明

P2-2 agent_weights 无校验即落库:
- validation 新增 AgentWeightsSchema / validate_agent_weights:
  未知专家名丢弃、越界值钳制、总和非 1 时归一化
- orchestrator 落库前对 agent_weights 做校验

P2-3 1x2 与比分不一致被静默修正:
- 仍以比分修正,但补 logger.warning 暴露 LLM 自相矛盾

P2-5/P2-6 prompt 缓存不可刷新 + 缓存键不含模板内容:
- 新增 clear_prompt_cache() 供改模板后显式失效
- 缓存键纳入模板内容 hash,模板一改缓存自动失效

P2-7 ingest/backtest/settle 接口无鉴权:
- 新增 require_admin_key 依赖(X-API-Key),
  ADMIN_API_KEY 未设置时放行并告警(不破坏本地开发)
- 挂到 3 个 ingest 接口 + backtest + eval/settle

P2-8 前端请求竞态 + 未使用游标分页:
- Matches.tsx 用递增 seq 丢弃过期响应,避免旧筛选结果覆盖新筛选
- 接入后端已有的 cursor 分页 + 「加载更多」按钮

附带: .env.example 补齐 LLM_TIMEOUT / 分档模型 / ADMIN_API_KEY;
tests 新增 10 个用例覆盖 P2-1/2/3。

frontend/src/pages/Matches.tsx

@@ -1,4 +1,4 @@
-import { useCallback, useEffect, useState } from 'react'
+import { useCallback, useEffect, useRef, useState } from 'react'
 
 interface Match {
   id: number
@@ -69,31 +69,69 @@ export default function Matches() {
   const [league, setLeague] = useState('E0')
   const [status, setStatus] = useState('scheduled')
   const [matches, setMatches] = useState<Match[]>([])
+  const [nextCursor, setNextCursor] = useState<string | null>(null)
+  const [loadingMore, setLoadingMore] = useState(false)
   const [loading, setLoading] = useState(false)
   const [predictingId, setPredictingId] = useState<number | null>(null)
   const [prediction, setPrediction] = useState<Prediction | null>(null)
   const [error, setError] = useState<string | null>(null)
   const [mode, setMode] = useState<'single' | 'multi'>('multi')
 
+  // 请求竞态防护:切换联赛/状态很快时,先发的慢请求可能后返回,
+  // 把旧结果覆盖到新筛选上。用递增序号只认最后一次请求的响应。
+  const loadSeq = useRef(0)
+  const predictSeq = useRef(0)
+
   const load = useCallback(async () => {
+    const seq = ++loadSeq.current
     setLoading(true)
+    // 切换筛选时作废进行中的「加载更多」,避免其标志位卡住
+    setLoadingMore(false)
     setError(null)
     try {
       const params = new URLSearchParams({ league, status, limit: '50' })
       const res = await fetch(`/api/v1/matches?${params}`)
+      if (seq !== loadSeq.current) return // 已有更新的请求,丢弃本次结果
       if (!res.ok) throw new Error(`HTTP ${res.status}`)
       const data = await res.json()
+      if (seq !== loadSeq.current) return
       setMatches(data.items)
+      setNextCursor(data.next_cursor ?? null)
     } catch (e) {
+      if (seq !== loadSeq.current) return
       setError(e instanceof Error ? e.message : String(e))
     } finally {
-      setLoading(false)
+      if (seq === loadSeq.current) setLoading(false)
     }
   }, [league, status])
 
+  // 加载下一页(游标分页)。后端已支持 cursor,前端此前未使用,
+  // 导致 limit=50 之后的数据永远看不到(见审查报告 P2-8)。
+  const loadMore = async () => {
+    if (!nextCursor || loadingMore) return
+    const seq = loadSeq.current // 不做自增:切换筛选会自增,这里只跟随当前序列
+    setLoadingMore(true)
+    try {
+      const params = new URLSearchParams({ league, status, limit: '50', cursor: nextCursor })
+      const res = await fetch(`/api/v1/matches?${params}`)
+      if (seq !== loadSeq.current) return
+      if (!res.ok) throw new Error(`HTTP ${res.status}`)
+      const data = await res.json()
+      if (seq !== loadSeq.current) return
+      setMatches(prev => [...prev, ...data.items])
+      setNextCursor(data.next_cursor ?? null)
+    } catch (e) {
+      if (seq !== loadSeq.current) return
+      setError(e instanceof Error ? e.message : String(e))
+    } finally {
+      if (seq === loadSeq.current) setLoadingMore(false)
+    }
+  }
+
   useEffect(() => { load() }, [load])
 
   const predict = async (matchId: number) => {
+    const seq = ++predictSeq.current
     setPredictingId(matchId)
     setError(null)
     setPrediction(null)
@@ -103,16 +141,19 @@ export default function Matches() {
         headers: { 'Content-Type': 'application/json' },
         body: JSON.stringify({ match_id: matchId, mode }),
       })
+      if (seq !== predictSeq.current) return
       if (!res.ok) {
         const t = await res.text()
         throw new Error(`HTTP ${res.status}: ${t}`)
       }
       const data = await res.json()
+      if (seq !== predictSeq.current) return
       setPrediction(data)
     } catch (e) {
+      if (seq !== predictSeq.current) return
       setError(e instanceof Error ? e.message : String(e))
     } finally {
-      setPredictingId(null)
+      if (seq === predictSeq.current) setPredictingId(null)
     }
   }
 
@@ -211,6 +252,16 @@ export default function Matches() {
         </table>
       </div>
 
+      {/* 分页: 加载更多 */}
+      {nextCursor && (
+        <div className="flex justify-center">
+          <button onClick={loadMore} disabled={loadingMore}
+            className="bg-white border text-gray-700 text-sm px-6 py-2 rounded hover:bg-gray-50 disabled:opacity-50">
+            {loadingMore ? '加载中...' : '加载更多'}
+          </button>
+        </div>
+      )}
+
       {/* 预测中指示 */}
       {predictingId && (
         <div className="bg-blue-50 border border-blue-200 text-blue-700 px-4 py-3 rounded text-sm flex items-center gap-2">