feat(portal-shell): wire dashboards to real data-ana queries (P1-2)

- add dashboard.graphql.ts with 6 real aggregate queries
  (teacherDashboard / studentDashboard / parentDashboard /
   adminDashboard / warnings / errorBookStats), snake_case aligned
- add dashboard.ts with 6 hooks + full domain model types
- add 4 role dashboard pages (teacher/student/parent/admin)
  using DashboardShell + StatCard + DashboardSection with
  loading / error / success tri-state
- update [[...route]]/page.tsx to redirect /shell -> /shell/{role}
- retire 6 fake contract queries and hooks (grades/homeworks/
  schedule/attendance/exams/announcements) and mark widget
  placeholders as migrated
- update universal.test.ts to drop retired hook tests
- mark ARCHITECTURE.md P1-2 as completed with acceptance evidence

apps/portal-shell/src/app/shell/admin/page.tsx

@@ -0,0 +1,121 @@
+"use client";
+
+import { Activity, Building2, GraduationCap, Users } from "lucide-react";
+
+import { useAdminDashboard } from "@/lib/api";
+import { DashboardShell } from "@/shared/components/dashboard/dashboard-shell";
+import { DashboardSection } from "@/shared/components/dashboard/dashboard-section";
+import { StatCard } from "@/shared/components/ui/stat-card";
+import { Card, CardContent } from "@/shared/components/ui/card";
+
+/**
+ * 管理员仪表盘（ARCHITECTURE.md §7.1 / §10 P1-2）
+ *
+ * 改接 data-ana 的 adminDashboard 真实聚合查询，替换原
+ * announcements 假契约 widget 查询。
+ *
+ * 关联：ARCHITECTURE.md §5.5 / §10 P1-2
+ */
+export default function AdminDashboardPage(): React.ReactElement {
+  const { data, loading, error } = useAdminDashboard();
+
+  if (loading) {
+    return (
+      <DashboardShell title="管理员仪表盘" description="全校概览">
+        <div className="grid grid-cols-1 gap-4 md:grid-cols-2 lg:grid-cols-4">
+          {Array.from({ length: 4 }).map((_, i) => (
+            <StatCard key={i} title="" value="" isLoading />
+          ))}
+        </div>
+      </DashboardShell>
+    );
+  }
+
+  if (error || !data) {
+    return (
+      <DashboardShell title="管理员仪表盘" description="全校概览">
+        <Card>
+          <CardContent className="py-8 text-center text-muted-foreground">
+            仪表盘数据加载失败，请稍后重试。
+          </CardContent>
+        </Card>
+      </DashboardShell>
+    );
+  }
+
+  return (
+    <DashboardShell
+      title="管理员仪表盘"
+      description="全校概览"
+      stats={
+        <>
+          <StatCard title="教师总数" value={data.total_teachers} icon={Users} />
+          <StatCard
+            title="学生总数"
+            value={data.total_students}
+            icon={GraduationCap}
+          />
+          <StatCard
+            title="班级总数"
+            value={data.total_classes}
+            icon={Building2}
+          />
+          <StatCard
+            title="全校平均分"
+            value={data.school_avg_score?.toFixed(1) ?? "--"}
+            icon={Activity}
+          />
+        </>
+      }
+    >
+      <DashboardSection title="近期预警" variant="list">
+        {data.recent_warnings ? (
+          <div className="space-y-2 text-sm">
+            <div className="flex items-center justify-between">
+              <span className="font-medium">
+                {data.recent_warnings.target_name ?? "--"}
+              </span>
+              <span className="text-muted-foreground">
+                {data.recent_warnings.severity ?? "--"}
+              </span>
+            </div>
+            <p className="text-xs text-muted-foreground">
+              类型：{data.recent_warnings.warning_type ?? "--"} · 当前值{" "}
+              {data.recent_warnings.current_value?.toFixed(1) ?? "--"} / 阈值{" "}
+              {data.recent_warnings.threshold?.toFixed(1) ?? "--"}
+            </p>
+          </div>
+        ) : (
+          <p className="text-sm text-muted-foreground">暂无预警</p>
+        )}
+      </DashboardSection>
+
+      <DashboardSection title="AI 用量" variant="card">
+        {data.ai_usage ? (
+          <div className="space-y-2 text-sm">
+            <div className="flex items-center justify-between">
+              <span className="text-muted-foreground">总请求</span>
+              <span className="font-medium">
+                {data.ai_usage.total_requests ?? "--"}
+              </span>
+            </div>
+            <div className="flex items-center justify-between">
+              <span className="text-muted-foreground">总 Token</span>
+              <span className="font-medium">
+                {data.ai_usage.total_tokens ?? "--"}
+              </span>
+            </div>
+            <div className="flex items-center justify-between">
+              <span className="text-muted-foreground">总费用（分）</span>
+              <span className="font-medium">
+                {data.ai_usage.total_cost_cents ?? "--"}
+              </span>
+            </div>
+          </div>
+        ) : (
+          <p className="text-sm text-muted-foreground">暂无 AI 用量数据</p>
+        )}
+      </DashboardSection>
+    </DashboardShell>
+  );
+}