Go client: port stream-alarms and acknowledge-alarm

Adds the session-less alarm CLI subcommands to mxgw-go. stream-alarms attaches
to the gateway's central alarm feed (--filter-prefix, --limit, --json — NDJSON,
one AlarmFeedMessage per line); acknowledge-alarm is a unary ack (--reference
required, --comment, --operator). StreamAlarms joins QueryActiveAlarms on the
public Client and is wired through the existing batch dispatcher via runWithIO.
SDK type aliases for StreamAlarmsRequest / AlarmFeedMessage / StreamAlarmsClient
land alongside the existing alarm types.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

clients/go/mxgateway/alarms_test.go

@@ -147,8 +147,8 @@ func TestQueryActiveAlarmsPassesFilterPrefix(t *testing.T) {
 	defer cleanup()
 
 	stream, err := client.QueryActiveAlarms(context.Background(), &pb.QueryActiveAlarmsRequest{
-		SessionId:          "session-1",
-		AlarmFilterPrefix:  "Tank01.",
+		SessionId:         "session-1",
+		AlarmFilterPrefix: "Tank01.",
 	})
 	if err != nil {
 		t.Fatalf("QueryActiveAlarms() error = %v", err)