message: smart filters headers test added
diff: @@ -13,6 +13,7 @@ import java.time.OffsetDateTime;
  import java.time.temporal.ChronoUnit;
  import java.util.ArrayList;
  import java.util.List;
  +import java.util.Map;
  import java.util.function.Predicate;
  import org.apache.commons.lang3.RandomStringUtils;
  import org.junit.jupiter.api.Nested;
  @@ -80,6 +81,13 @@ class MessageFiltersTest {
  assertFalse(f.test(msg().offset(200L)));
  }
  + @Test
  + void canCheckHeaders() {
  + var f = groovyScriptFilter("headers.size() == 2 && headers['k1'] == 'v1'");
  + assertTrue(f.test(msg().headers(Map.of("k1", "v1", "k2", "v2"))));
  + assertFalse(f.test(msg().headers(Map.of("k1", "unexpected", "k2", "v2"))));
  + }
  +
  @Test
  void canCheckTimestampMs() {
  var ts = OffsetDateTime.now();
  