Segmenting on a custom location field

Hi DavidO, thanks for this.

What I was trying to understand here was whether it would be possible do e.g., radius checks on specific locations without having to track users via the SDK. I've since realised that we can explicitly set the `current location` user property (https://www.braze.com/docs/user_guide/engagement_tools/locations_and_geofences/location_tracking/#hard-setting-the-default-location-attribute). So, although this isn't a custom property it would probably satisfy what I'm trying to do.

However, my next blocker is how to trigger this dynamically. E.g, I'd want to set the radius to include users for to be a dynamic property, different for each invocation of the canvas (I'm triggering these via API call). I think the best bet here would be using connected audience filters, but I can't see from the Connected Audience Filter docs (https://www.braze.com/docs/api/objects_filters/connected_audience/) whether it's possible to trigger a condition something like "Most recent location must be within a circle of X Miles" etc. Seems like this might be missing from connected audience filters... or I've not worked out how to do it yet.