fix: 花名册合同风险统计与风险中心不一致

花名册快捷筛选标签基于当前页数据统计，改为后端返回全局RiskItem统计
- 后端roster API返回globalRiskStats(expiring/expired/unsigned)
- 前端优先使用全局统计，fallback到当前页统计

backend/src/routes/roster.routes.ts

@@ -210,6 +210,13 @@ router.get('/', authMiddleware, async (req: AuthRequest, res, next) => {
       result = result.slice(skip, skip + pageSize)
     }
 
+    // 全局合同风险统计（基于 RiskItem，与风险中心同口径）
+    const [globalExpiring, globalExpired, globalUnsigned] = await Promise.all([
+      prisma.riskItem.count({ where: { orgId: req.user!.orgId, status: 'PENDING', type: 'CONTRACT', level: 'MEDIUM' } }),
+      prisma.riskItem.count({ where: { orgId: req.user!.orgId, status: 'PENDING', type: 'CONTRACT', level: 'HIGH' } }),
+      prisma.riskItem.count({ where: { orgId: req.user!.orgId, status: 'PENDING', type: 'ONBOARDING' } }),
+    ])
+
     res.json({
       success: true,
       data: result,
@@ -219,6 +226,11 @@ router.get('/', authMiddleware, async (req: AuthRequest, res, next) => {
         total: filteredTotal,
         totalPages: Math.ceil(filteredTotal / pageSize),
       },
+      globalRiskStats: {
+        expiring: globalExpiring,
+        expired: globalExpired,
+        unsigned: globalUnsigned,
+      },
     })
   } catch (err) {
     next(err)