Allow editing Apt/Unit after property creation

Allow hosts to edit the Apt/Unit field in Property Details after a property has been created. Problem: For condos or multi-unit buildings, multiple properties can share the same street address and only differ by unit number. If the unit number is missing or not saved correctly during setup/import, hosts cannot update it because the Location fields are locked. Impact: This causes confusion for guests and teammates/cleaners, especially when arrival instructions or teammate tasks only show the street address without the unit number. Hosts may also avoid adding the unit number to the public listing title for privacy and safety reasons. Suggested solution: Make the Apt/Unit field editable post-creation, or provide a support/admin-safe way to update it without changing the public listing title.