chore: gitignore mul-data/ directory

Raw scraped data is archived in mul-data.zip; ignore the extracted directory.

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

Author: graylikeme

.gitignore

@@ -4,6 +4,9 @@
 *.swo
 .claude/settings.local.json
 
+# MUL scraped data (archived in mul-data.zip)
+mul-data/
+
 # Terraform
 infra/.terraform/
 infra/*.tfstate*