Update docs from [email protected]

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in the gateway repository.

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Author: Frostman

docs/reference/gateway-api.md.gen

@@ -480,6 +480,7 @@ _Appears in:_
 | `agentVersion` _string_ | AgentVersion is the version of the gateway agent |  |  |
 | `lastAppliedTime` _[Time](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.32/#time-v1-meta)_ | Time of the last successful configuration application |  |  |
 | `lastAppliedGen` _integer_ | Generation of the last successful configuration application |  |  |
+| `lastHeartbeat` _[Time](https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.32/#time-v1-meta)_ | Time of the last heartbeat from the agent |  |  |
 | `state` _[GatewayState](#gatewaystate)_ | State represents collected data from the dataplane API that includes FRR as well |  |  |