feat: T1.4 健康度仪表盘 — 后端聚合 API + 前端驾驶舱

- 后端：dashboard 路由（summary 聚合 + scores 列表）
- 前端：驾驶舱首页（KPI 卡片 + 健康度概览）
- 测试：4 个仪表盘测试（总计 37 tests passed）
- 前端构建 12 路由成功

frontend/src/app/(investor)/dashboard/page.tsx

@@ -1,15 +1,155 @@
-/** 投资人端驾驶舱首页 — 占位页面。 */
+"use client";
 
+import { useEffect, useState } from "react";
+import { Building2, Heart, AlertTriangle, FileText, TrendingUp, TrendingDown, Minus } from "lucide-react";
+import Link from "next/link";
+import { getDashboardSummary, type DashboardSummary } from "@/lib/dashboard";
 import { LoadingSpinner } from "@/components/shared/LoadingSpinner";
+import { EmptyState } from "@/components/shared/EmptyState";
+import { HealthScoreBadge } from "@/components/shared/HealthScoreBadge";
+
+/**
+ * 投资人端 — 驾驶舱首页。
+ */
+export default function InvestorDashboardPage() {
+  const [summary, setSummary] = useState<DashboardSummary | null>(null);
+  const [isLoading, setIsLoading] = useState(true);
+
+  useEffect(() => {
+    async function load() {
+      try {
+        const resp = await getDashboardSummary();
+        if (resp.data) setSummary(resp.data);
+      } catch {
+        // ignore
+      } finally {
+        setIsLoading(false);
+      }
+    }
+    load();
+  }, []);
+
+  if (isLoading) {
+    return (
+      <div className="space-y-6">
+        <h1 className="text-2xl font-bold text-foreground">投资机构驾驶舱</h1>
+        <div className="flex justify-center py-20">
+          <LoadingSpinner />
+        </div>
+      </div>
+    );
+  }
+
+  const kpis = [
+    {
+      label: "被投企业",
+      value: summary?.total_companies ?? 0,
+      icon: Building2,
+      href: "/companies",
+      color: "text-[var(--investor-primary)]",
+      bg: "bg-[var(--investor-primary)]/10",
+    },
+    {
+      label: "平均健康度",
+      value: summary?.avg_health_score?.toFixed(1) ?? "0.0",
+      icon: Heart,
+      href: "/companies",
+      color: "text-emerald-600",
+      bg: "bg-emerald-50",
+    },
+    {
+      label: "高风险事件",
+      value: summary?.high_risk_count ?? 0,
+      icon: AlertTriangle,
+      href: "/risks",
+      color: "text-amber-600",
+      bg: "bg-amber-50",
+    },
+    {
+      label: "待审月报",
+      value: summary?.pending_reports ?? 0,
+      icon: FileText,
+      href: "/reports",
+      color: "text-blue-600",
+      bg: "bg-blue-50",
+    },
+  ];
 
-export default function InvestorHomePage() {
   return (
     <div className="space-y-6">
       <div>
         <h1 className="text-2xl font-bold text-foreground">投资机构驾驶舱</h1>
         <p className="mt-1 text-sm text-muted-foreground">Portfolio 全局健康度与风险概览</p>
       </div>
-      <LoadingSpinner className="py-20" size={32} />
+
+      {/* KPI 卡片 */}
+      <div className="grid gap-4 sm:grid-cols-2 lg:grid-cols-4">
+        {kpis.map((kpi) => (
+          <Link
+            key={kpi.label}
+            href={kpi.href}
+            className="rounded-lg border bg-white p-5 shadow-sm transition-all hover:shadow-md"
+          >
+            <div className="flex items-center justify-between">
+              <div>
+                <p className="text-sm text-muted-foreground">{kpi.label}</p>
+                <p className="mt-1 text-2xl font-bold text-foreground">{kpi.value}</p>
+              </div>
+              <div className={`flex h-12 w-12 items-center justify-center rounded-lg ${kpi.bg}`}>
+                <kpi.icon className={kpi.color} size={24} aria-hidden="true" />
+              </div>
+            </div>
+          </Link>
+        ))}
+      </div>
+
+      {/* 健康度概览 */}
+      <div className="rounded-lg border bg-white p-5 shadow-sm">
+        <div className="mb-4 flex items-center justify-between">
+          <h2 className="text-lg font-semibold">健康度概览</h2>
+          <Link href="/companies" className="text-sm text-[var(--investor-primary)] hover:underline">
+            查看全部 →
+          </Link>
+        </div>
+
+        {summary && summary.recent_scores.length > 0 ? (
+          <div className="space-y-3">
+            {summary.recent_scores.map((score) => (
+              <div key={score.id} className="flex items-center justify-between border-b pb-3 last:border-0 last:pb-0">
+                <div className="flex items-center gap-3">
+                  <HealthScoreBadge score={Math.round(score.total_score)} />
+                  <div>
+                    <p className="text-sm font-medium">企业 ID: {score.company_id.slice(0, 8)}...</p>
+                    <p className="text-xs text-muted-foreground">
+                      {new Date(score.calculated_at).toLocaleDateString("zh-CN")}
+                    </p>
+                  </div>
+                </div>
+                <div className="flex items-center gap-4 text-sm">
+                  {score.financial_score !== null && (
+                    <span className="text-muted-foreground">财务: {score.financial_score.toFixed(0)}</span>
+                  )}
+                  {score.operational_score !== null && (
+                    <span className="text-muted-foreground">经营: {score.operational_score.toFixed(0)}</span>
+                  )}
+                  {score.trend && (
+                    <span className={`flex items-center gap-1 ${
+                      score.trend === "up" ? "text-emerald-600" :
+                      score.trend === "down" ? "text-rose-600" : "text-muted-foreground"
+                    }`}>
+                      {score.trend === "up" && <TrendingUp size={14} aria-hidden="true" />}
+                      {score.trend === "down" && <TrendingDown size={14} aria-hidden="true" />}
+                      {score.trend === "stable" && <Minus size={14} aria-hidden="true" />}
+                    </span>
+                  )}
+                </div>
+              </div>
+            ))}
+          </div>
+        ) : (
+          <EmptyState title="暂无评分数据" description="健康度评分将在月报提交后自动计算" />
+        )}
+      </div>
     </div>
   );
 }