Refine "checkpoint on refresh" error handling

Closes gh-31096

spring-context/src/main/java/org/springframework/context/support/DefaultLifecycleProcessor.java

@@ -108,6 +108,9 @@ public class DefaultLifecycleProcessor implements LifecycleProcessor, BeanFactor
 		if (!NativeDetector.inNativeImage() && ClassUtils.isPresent("org.crac.Core", getClass().getClassLoader())) {
 			this.cracResource = new CracDelegate().registerResource();
 		}
+		else if (checkpointOnRefresh) {
+			throw new IllegalStateException("Checkpoint on refresh requires a CRaC-enabled JVM and 'org.crac:crac' on the classpath");
+		}
 	}