feat(python-client): operator credentials on acknowledge-alarm

Claude-Session: https://claude.ai/code/session_016J6isfcgqy4SB2RK3ZvFvT

clients/python/README.md

@@ -111,9 +111,15 @@ MXAccess commands and preserve raw replies on typed command exceptions.
 For alarms, the client exposes `GatewayClient.query_active_alarms` (one-shot
 snapshot), `GatewayClient.stream_alarms` (async generator yielding alarm-feed
 messages from the gateway's central monitor), and
-`GatewayClient.acknowledge_alarm` (ack by alarm reference, optional comment
-and ack target). Cancel the surrounding task or `aclose()` the iterator to
-terminate the stream.
+`GatewayClient.acknowledge_alarm` (ack by alarm reference with an optional
+comment). The ack is made as the operator: set `operator_user` (required) and
+`operator_password` (may be empty) and optionally `operator_domain` on
+`AcknowledgeAlarmRequest`. The gateway authenticates the operator and writes the
+comment to the alarm's `AckMsg`, so the alarm history records the operator. The
+password is redacted from any raised error.
+
+Cancel the surrounding task or `aclose()` an alarm iterator to terminate the
+stream.
 
 `ActiveAlarmSnapshot.from_truncated_snapshot` reports that the record came from
 a provider fetch which hit the per-fetch cap: the snapshot set may omit active
@@ -457,7 +463,7 @@ mxgw-py add-item --session-id <id> --server-handle 1 --item Object.Attribute --j
 mxgw-py advise --session-id <id> --server-handle 1 --item-handle 2 --json
 mxgw-py stream-events --session-id <id> --max-events 1 --json
 mxgw-py stream-alarms --max-messages 4 --json
-mxgw-py acknowledge-alarm --reference "\\Galaxy\Area001.Pump001.PumpFault" --json
+mxgw-py acknowledge-alarm --reference "\\Galaxy\Area001.Pump001.PumpFault" --operator operator1 --operator-password-env MXGATEWAY_OPERATOR_PASSWORD --json
 mxgw-py write --session-id <id> --server-handle 1 --item-handle 2 --type int32 --value 123 --json
 ```