fix(mining): 市场环境数据缺失时挖掘启动即失败并前置提示

用户在未计算市场环境的数据目录跑挖掘: 搜索阶段的 regime 评估被
evaluator 软捕获成 error 字符串, 整轮嵌套搜索照常跑完后, artifacts
阶段的 _regime_date_count 硬抛 ValueError, 计算全部浪费且只在最后
给出指引。

- mining_runtime: require_regime 时在因子面板就绪后立即用与
  artifacts 相同的 fold 口径预构建一次 regime mask (required 区间取
  全部外层 fold 测试窗并集), 数据为空/覆盖不完整即刻带指引消息终止
- MiningWorkbench: 启动前查询 /api/regime/latest, 未计算时侧栏显示
  警告横幅(直达数据页)并在开始时 toast 阻止, 避免产生必败的运行记录
- 测试: 缺数据 fail-fast / 覆盖充足通过 / fold 窗口内缺口报错 三例

frontend/src/pages/backtest/MiningWorkbench.tsx

@@ -1,6 +1,6 @@
 import { useEffect, useMemo, useRef, useState } from 'react'
 import { useMutation, useQuery, useQueryClient } from '@tanstack/react-query'
-import { useSearchParams } from 'react-router-dom'
+import { Link, useSearchParams } from 'react-router-dom'
 import {
   AlertTriangle,
   CheckCircle2,
@@ -303,6 +303,7 @@ export function MiningWorkbench() {
     enabled: validDateRange,
     staleTime: 30_000,
   })
+  const regimeLatestQuery = useQuery({ queryKey: QK.regimeLatest, queryFn: api.regimeLatest, staleTime: 60_000 })
   const configQuery = useQuery({ queryKey: QK.miningConfig, queryFn: api.miningConfig })
 
   useEffect(() => {
@@ -454,6 +455,18 @@ export function MiningWorkbench() {
       )
       return
     }
+    if (regimeLatestQuery.isPending || regimeLatestQuery.isFetching) {
+      toast('正在核验市场环境数据，请稍候', 'error')
+      return
+    }
+    if (regimeLatestQuery.isError || !regimeLatestQuery.data) {
+      toast('无法核验市场环境数据，请检查数据状态后重试', 'error')
+      return
+    }
+    if (!regimeLatestQuery.data.row) {
+      toast('尚未计算市场环境数据：挖掘含市场环境分组评估，请先在数据页完成市场环境计算', 'error')
+      return
+    }
     const commissionBps = parseBoundedNumber(draft.commissionBps, '佣金', 0, 500)
     const stampTaxBps = parseBoundedNumber(draft.stampTaxBps, '印花税', 0, 500)
     const slippageBps = parseBoundedNumber(draft.slippageBps, '滑点', 0, 1000)
@@ -567,6 +580,12 @@ export function MiningWorkbench() {
             )}
           </section>
 
+          {regimeLatestQuery.data && !regimeLatestQuery.data.row && (
+            <Link to="/data" className="block rounded-btn border border-warning/40 bg-warning/5 px-2 py-1.5 text-[9px] leading-4 text-warning transition-colors hover:border-warning/70">
+              尚未计算市场环境数据 — 挖掘含市场环境分组评估，缺少时启动即校验失败。<span className="underline underline-offset-2">前往数据页完成市场环境计算 →</span>
+            </Link>
+          )}
+
           <section className="border-t border-border pt-3">
             <div className="mb-2 flex items-center justify-between">
               <span className="flex items-center gap-1.5 text-[10px] font-semibold text-secondary"><FlaskConical className="h-3 w-3" />因子目录</span>