agent-go: engineReport gains singBoxVersion. The probe runs
`sing-box version` once, parses the version token from its first line
('unknown' from unstamped builds reports empty), and caches it keyed by
the binary's mtime+size — re-probed only when an engine install/update
replaces the file. Steady-state heartbeats pay one stat, no subprocess.
Agent version stays 0.6.8.
panel-go: EngineState.singBoxVersion persisted from heartbeats (old
agents without the field keep showing '-'), servers table core-version
column now renders it. Golden gains heartbeatWithEngine +
serversAfterEngineHeartbeat sections locking the full chain, plus a
listen-address (<hostip>) normalization for the sandbox bind address.
singboxversion_test.go covers parsing, cache hits, and re-probe on
binary replacement.
Agents (Go + Node) now report the resource IDs they actually hold in
each heartbeat. When an expected resource is missing locally (e.g. the
node's /etc/nexusgate state was wiped and only the agent restarted, so
no re-enrollment happens), the panel re-queues applies for just the
affected nodes via reconcileFromHeartbeat: gated on no queued/running
jobs for the server (in-flight jobs are never failed by this path) and
throttled to one trigger per server per 120s, audited as
system:heartbeat. reconcileServer gains optional onlyNodeIds /
failInFlight parameters; the enrollment call is unchanged. Heartbeats
without a resources array (old agents) behave exactly as before.
aaaamoooo