fix: add logging for IOException catch and test for exception propagation

Address Sourcery review feedback: log a warning when a container engine
is not available instead of silently returning empty, and add a test
verifying that non-IO RuntimeExceptions still propagate.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ruromero

src/main/java/io/github/guacsec/trustifyda/image/ImageUtils.java

@@ -24,6 +24,7 @@
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.fasterxml.jackson.databind.node.TextNode;
 import com.github.packageurl.MalformedPackageURLException;
+import io.github.guacsec.trustifyda.logging.LoggersFactory;
 import io.github.guacsec.trustifyda.tools.Operations;
 import io.github.guacsec.trustifyda.utils.Environment;
 import java.io.File;
@@ -35,11 +36,14 @@
 import java.util.Map;
 import java.util.Objects;
 import java.util.function.Supplier;
+import java.util.logging.Logger;
 import java.util.stream.Collectors;
 import java.util.stream.StreamSupport;
 
 public class ImageUtils {
 
+  private static final Logger LOG = LoggersFactory.getLogger(ImageUtils.class.getName());
+
   static final String TRUSTIFY_DA_SYFT_CONFIG_PATH = "TRUSTIFY_DA_SYFT_CONFIG_PATH";
   static final String TRUSTIFY_DA_SYFT_IMAGE_SOURCE = "TRUSTIFY_DA_SYFT_IMAGE_SOURCE";
   static final String TRUSTIFY_DA_IMAGE_PLATFORM = "TRUSTIFY_DA_IMAGE_PLATFORM";
@@ -286,6 +290,9 @@ static String hostInfo(String engine, String info) {
       output = Operations.runProcessGetFullOutput(null, cmd, null);
     } catch (RuntimeException e) {
       if (e.getCause() instanceof IOException) {
+        LOG.warning(
+            String.format(
+                "Container engine '%s' not available: %s", exec, e.getCause().getMessage()));
         return "";
       }
       throw e;

src/test/java/io/github/guacsec/trustifyda/image/ImageUtilsTest.java

@@ -27,6 +27,8 @@
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.AdditionalMatchers.aryEq;
 import static org.mockito.ArgumentMatchers.any;
@@ -553,6 +555,27 @@ void test_host_info_no_docker_path() {
     }
   }
 
+  @Test
+  void test_host_info_other_runtime_exceptions_propagate() {
+    try (MockedStatic<Operations> mock = Mockito.mockStatic(Operations.class)) {
+      RuntimeException expected = new RuntimeException("non-io-error");
+
+      mock.when(() -> Operations.getCustomPathOrElse(eq("docker"))).thenReturn("docker");
+
+      mock.when(() -> Operations.getExecutable(eq("docker"), any())).thenReturn("docker");
+
+      mock.when(
+              () ->
+                  Operations.runProcessGetFullOutput(
+                      isNull(), aryEq(new String[] {"docker", "info"}), isNull()))
+          .thenThrow(expected);
+
+      RuntimeException thrown =
+          assertThrows(RuntimeException.class, () -> ImageUtils.hostInfo("docker", "info"));
+      assertSame(expected, thrown);
+    }
+  }
+
   @Test
   @SetSystemProperty(key = "TRUSTIFY_DA_DOCKER_PATH", value = mockDockerPath)
   @SetSystemProperty(key = "PATH", value = mockPath)