HHH-16548 document CWD class scanning

Author: gavinking

hibernate-core/src/main/java/org/hibernate/jpa/HibernatePersistenceConfiguration.java

@@ -66,6 +66,12 @@
  * <li>JVM {@linkplain System#getProperties() system properties}, and
  * <li>properties specified in {@code hibernate.properties}.
  * </ul>
+ * <p>
+ * When {@linkplain org.hibernate.cfg.PersistenceSettings#SCANNER_DISCOVERY
+ * entity discovery} is explicitly enabled, and {@code hibernate-scan-jandex}
+ * or some other {@link org.hibernate.boot.archive.scan.spi.ScannerFactory}
+ * service is available, the current working directly is scanned for entity
+ * classes, alleviating the program of the need to call {@link #managedClass}.
  *
  * @apiNote The specification explicitly encourages implementors to extend
  *          {@link PersistenceConfiguration} to accommodate vendor-specific