feat(WEB): 결재/회계/품목 관리 개선

- ApprovalLineSection/ReferenceSection: 결재선 설정 개선
- DepositManagement/WithdrawalManagement: 입출금 관리 UI 개선
- bills/pricing-management 페이지 수정
- ItemDetailClient: 품목 상세 표시 개선

src/app/[locale]/(protected)/accounting/bills/page.tsx

@@ -47,7 +47,7 @@ async function getBills(params: {
     queryParams.append('per_page', '20');
 
     const response = await fetch(
-      `${process.env.NEXT_PUBLIC_API_URL}/api/v1/bills?${queryParams.toString()}`,
+      `${process.env.API_URL}/api/v1/bills?${queryParams.toString()}`,
       { method: 'GET', headers, cache: 'no-store' }
     );
 

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

@@ -150,7 +150,7 @@ async function getItemsList(): Promise<ItemApiData[]> {
     const headers = await getApiHeaders();
 
     const response = await fetch(
-      `${process.env.NEXT_PUBLIC_API_URL}/api/v1/items?group_id=1&size=100`,
+      `${process.env.API_URL}/api/v1/items?group_id=1&size=100`,
       {
         method: 'GET',
         headers,
@@ -183,7 +183,7 @@ async function getPricingList(): Promise<PriceApiItem[]> {
     const headers = await getApiHeaders();
 
     const response = await fetch(
-      `${process.env.NEXT_PUBLIC_API_URL}/api/v1/pricing?size=100`,
+      `${process.env.API_URL}/api/v1/pricing?size=100`,
       {
         method: 'GET',
         headers,