fix: [misc] 거래처 카운트 수정 + 생산현황판 통계 API 교체

- 거래처 목록 카운트를 stats API 호출로 교체
- 생산현황판 대시보드 통계를 work-orders/stats API 활용

src/app/[locale]/(protected)/sales/client-management-sales-admin/page.tsx

@@ -94,22 +94,17 @@ export default function CustomerAccountManagementPage() {
   // 전체 통계 로드 (최초 1회만)
   const loadTotalStats = useCallback(async () => {
     try {
-      // 전체 데이터 조회 (검색 조건 없이)
-      const response = await fetch("/api/proxy/clients?size=1000");
+      const response = await fetch("/api/proxy/clients/stats");
       if (response.ok) {
         const result = await response.json();
         if (result.success && result.data) {
-          const allClients = result.data.data || [];
+          const data = result.data;
           setTotalStats({
-            total: result.data.total || allClients.length,
-            purchase: allClients.filter((c: { client_type?: string }) =>
-              c.client_type === "매입" || c.client_type === "매입매출"
-            ).length,
-            sales: allClients.filter((c: { client_type?: string }) =>
-              c.client_type === "매출" || c.client_type === "매입매출"
-            ).length,
-            active: allClients.filter((c: { is_active?: boolean }) => c.is_active === true).length,
-            inactive: allClients.filter((c: { is_active?: boolean }) => c.is_active === false).length,
+            total: data.total ?? 0,
+            purchase: (data.purchase ?? 0) + (data.both ?? 0),
+            sales: (data.sales ?? 0) + (data.both ?? 0),
+            active: data.active ?? 0,
+            inactive: data.inactive ?? 0,
           });
         }
       }