Listing-quality export: add Property Group data

Problem: The Airbnb listing-quality export (CSV) doesn't include property-group data. Without it, there's no way to filter or pivot the exported data by property group inside the sheet.

Request: Add property-group membership to the listing-quality export so each listing row carries its group(s), enabling filtering/pivoting by group in the exported file.

Detail:

• A listing can belong to more than one group at a time, so the export needs to handle multiple group memberships per row.
• Should respect the existing export columns/filters (no regression).

Acceptance criteria:

• Export includes property-group data per listing.
• User can filter/pivot the exported sheet by property group.
• No regression to existing export columns.