fix: Ensure upload preview modal opens and add debug logs

src/main.ts

@@ -126,6 +126,8 @@ function initApp() {
     });
   } catch (e) { console.error('❌ Initialization failed:', e); }
 
+  console.log('🚀 ITAM App Version 2.1.0 Loaded');
+
   // 버튼 이벤트 바인딩
   document.getElementById('btn-download-template')?.addEventListener('click', () => downloadTemplate());
   document.getElementById('btn-export-excel')?.addEventListener('click', () => exportToExcel(state.masterData));
@@ -134,8 +136,10 @@ function initApp() {
   uploadInput?.addEventListener('change', async (e) => {
     const file = (e.target as HTMLInputElement).files?.[0];
     if (file) {
+      console.log('📂 File selected:', file.name);
       try {
         const data = await parseExcel(file);
+        console.log('📊 Parsed data keys:', Object.keys(data));
         openUploadPreview(data);
         // Clear input so same file can be selected again
         uploadInput.value = '';