feat(statistics): '업체별 발주통계' 명확화 + SHIPPED 필터 제거

- 화면 제목: '통계 — 업체별 월간 매출' → '업체별 발주통계 (월별)'
- 메뉴명: '월간 매출' → '업체별 발주통계' (운영 DB menu_info 9000501)
- statistics/monthly API: status IN 에서 SHIPPED (dead code) 제거
- 기존 기능 그대로: 년/월 선택, 업체별 합계 + 면세/과세 분리, 엑셀 다운로드

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/app/(main)/m/admin/statistics/page.tsx

@@ -68,7 +68,7 @@ export default function StatisticsPage() {
   return (
     <div className="space-y-4">
       <div className="flex flex-wrap items-center justify-between gap-2">
-        <h1 className="text-xl sm:text-2xl font-bold">통계 — 업체별 월간 매출</h1>
+        <h1 className="text-xl sm:text-2xl font-bold">업체별 발주통계 (월별)</h1>
         <button
           onClick={onExport}
           disabled={rows.length === 0}

src/app/api/m/statistics/monthly/route.ts

@@ -20,7 +20,7 @@ export async function POST(req: NextRequest) {
      LEFT JOIN user_info U ON U.user_id = O.customer_objid
      WHERE EXTRACT(YEAR FROM O.order_date) = $1
        AND EXTRACT(MONTH FROM O.order_date) = $2
-       AND O.status IN ('APPROVED', 'SHIPPED', 'INVOICED', 'PAID')
+       AND O.status IN ('APPROVED', 'INVOICED', 'PAID')
        AND COALESCE(O.is_del,'N') != 'Y'
      GROUP BY U.user_name
      ORDER BY "TOTAL" DESC`,