Adds new metrics for:
- Dropped UDP datagrams for reads and write paths
- Dropped ICMP packets for write paths
- Failures that preemptively close UDP flows
Closes TUN-9882
Make sure to enforce snapshots of features and client information for each connection
so that the feature information can change in the background. This allows for new features
to only be applied to a connection if it completely disconnects and attempts a reconnect.
Updates the feature refresh time to 1 hour from previous cloudflared versions which
refreshed every 6 hours.
Closes TUN-9319
Devin Carr