feat(WEB): 전체 페이지 ?mode= URL 네비게이션 패턴 적용

- 등록(?mode=new), 상세(?mode=view), 수정(?mode=edit) URL 패턴 일괄 적용
- 중복 패턴 제거: /edit?mode=edit → ?mode=edit (16개 파일)
- 제목 일관성: {기능} 등록/상세/수정 패턴 적용
- 검수 체크리스트 문서 추가 (79개 페이지)
- UniversalListPage, IntegratedDetailTemplate 공통 컴포넌트 개선

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/components/accounting/BadDebtCollection/BadDebtDetail.tsx

@@ -137,7 +137,7 @@ export function BadDebtDetail({ mode, recordId, initialData }: BadDebtDetailProp
     if (isNewMode) {
       router.push('/ko/accounting/bad-debt-collection');
     } else {
-      router.push(`/ko/accounting/bad-debt-collection/${recordId}`);
+      router.push(`/ko/accounting/bad-debt-collection/${recordId}?mode=view`);
     }
   }, [router, recordId, isNewMode]);
 
@@ -163,7 +163,7 @@ export function BadDebtDetail({ mode, recordId, initialData }: BadDebtDetailProp
         const result = await updateBadDebt(recordId!, formData);
         if (result.success) {
           toast.success('악성채권이 수정되었습니다.');
-          router.push(`/ko/accounting/bad-debt-collection/${recordId}`);
+          router.push(`/ko/accounting/bad-debt-collection/${recordId}?mode=view`);
         } else {
           toast.error(result.error || '수정에 실패했습니다.');
         }

src/components/accounting/BadDebtCollection/index.tsx

@@ -98,7 +98,7 @@ export function BadDebtCollection({ initialData, initialSummary }: BadDebtCollec
   // ===== 핸들러 =====
   const handleRowClick = useCallback(
     (item: BadDebtRecord) => {
-      router.push(`/ko/accounting/bad-debt-collection/${item.id}`);
+      router.push(`/ko/accounting/bad-debt-collection/${item.id}?mode=view`);
     },
     [router]
   );