fix: normalize inline numbered lists in CSV export

Converts "1) Item. 2) Item." patterns to line-separated items within
quoted CSV cells, matching the frontend normalizeToMarkdown behavior.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/src/services/csvExportService.ts

@@ -217,7 +217,10 @@ class CSVExportService {
     if (!value) return '';
 
     // Normalize line endings but preserve newlines for readability in spreadsheet cells
-    const cleanValue = value.replace(/\r\n/g, '\n').replace(/\r/g, '\n').trim();
+    let cleanValue = value.replace(/\r\n/g, '\n').replace(/\r/g, '\n').trim();
+
+    // Convert inline numbered lists "1) ... 2) ..." to line-separated items for readable cells
+    cleanValue = cleanValue.replace(/\.\s+(\d+)\)\s/g, '.\n$1) ');
 
     // If value contains comma, quote, or newline, wrap in quotes and escape internal quotes
     // Excel/Google Sheets render newlines within quoted cells correctly