Returns all active platform connections for the authenticated customer.
Use this to verify which platforms are connected after calling /connect.
POST /connect.
The response is an array of connection objects. Each includes the platform name, connection
status, when it was established, and how many entity mappings exist for that platform.
If no platforms are connected, the connections array is empty.
active are returned. If a connect call failed mid-flight, the
connection may be in seeding or error state and will not appear in this response. Retry the
POST /connect call to re-seed.