Stork server /metrics endpoint should report the free addresses in the shared networks

Currently there are the following shared_network statistics from the Stork server /metrics

# HELP storkserver_shared_network_address_utilization Shared-network address utilization
# TYPE storkserver_shared_network_address_utilization gauge
storkserver_shared_network_address_utilization{name="test-shared-network-1"} 0
storkserver_shared_network_address_utilization{name="test-shared-network-2"} 0
# HELP storkserver_shared_network_pd_utilization Shared-network delegated-prefix utilization
# TYPE storkserver_shared_network_pd_utilization gauge
storkserver_shared_network_pd_utilization{name="test-shared-network-1"} 0
storkserver_shared_network_pd_utilization{name="test-shared-network-2"} 0

My understanding is that these contain percentages of addresses used. A customer would like to also see the remaining free addresses count in the shared_network statistics in /metrics so that alerts could more effectively shown by a floor of the number of addresses left (percentages aren't as effective because of different sized shared_networks. For example, 99% of 20,000 addresses is a large number (200 free addresses) compared to 99% of 254 addresses (2 free addresses).

To be clear: The Stork agent /metrics do not seem to contain shared_network statistics at all. The above refers to Stork server /metrics endpoint.

SF1912