refactor: integrate software assets into unified schema and optimize backend API

src/core/utils.ts

@@ -30,7 +30,13 @@ export function formatInline(value: any): string {
  * 날짜 문자열 포맷팅 (YYYY.MM.DD -> YYYY-MM-DD)
  */
 export function normalizeDate(dateStr: string): string {
-  return (dateStr || '').replace(/\./g, '-').trim();
+  if (!dateStr) return '';
+  let str = String(dateStr).replace(/\./g, '-').trim();
+  // YYYYMM 형식 처리 (6자리 숫자)
+  if (/^\d{6}$/.test(str)) {
+    return `${str.substring(0, 4)}-${str.substring(4, 6)}`;
+  }
+  return str;
 }
 
 /**