When multiple cluster nodes register sensor-proxy, each registration
was overwriting the previous node's control token on the shared
PVEInstance. This caused "Proxy token not recognized" errors on all
but the last-registered node.
Changes:
- Add TemperatureProxyControlToken field to ClusterEndpoint struct
- Store control tokens per-endpoint for cluster registrations
- Check both instance-level and endpoint-level tokens when validating
Related to #738
rcourtman
f8c7a30d28