Gaia integration overwrites existing property when sending a second risk profile for the same client

When a second risk profile is sent to Gaia for the same client, it overwrites the first property rather than creating a new entry. This makes it impossible to maintain multiple properties for one client in Gaia simultaneously.

Confirmed example: an agency quoted a client's primary residence, then a rental property. After sending the second profile, only the rental appeared in Gaia — the primary was gone. The agency currently has no way to have both properties in Gaia at the same time.

The Gaia API appears to support a property index parameter that would prevent overwriting. RiskAdvisor should expose this so agents can specify whether they're sending a first, second, or Nth property for a client.