Ignore smart-builder core extension, if present. (#916)

Add new daemon param to ignore some extensions, make default to ignore takari-smart-builder as it is used by mvnd itself as well.

Fixes #912

common/src/main/java/org/mvndaemon/mvnd/common/Environment.java

@@ -213,6 +213,18 @@ public enum Environment {
      * Internal option to specify the list of maven extension to register.
      */
     MVND_CORE_EXTENSIONS("mvnd.coreExtensions", null, null, OptionType.STRING, Flags.DISCRIMINATING | Flags.INTERNAL),
+    /**
+     * Internal option to specify comma separated list of maven extension G:As to exclude (to not load them from
+     * .mvn/extensions.xml). This option makes possible for example that a project that with vanilla Maven would
+     * use takari-smart-builder extension, remain buildable with mvnd (where use of this extension would cause issues).
+     * Value is expected as comma separated {@code g1:a1,g2:a2} pairs.
+     */
+    MVND_CORE_EXTENSIONS_EXCLUDE(
+            "mvnd.coreExtensionsExclude",
+            null,
+            "io.takari.maven:takari-smart-builder",
+            OptionType.STRING,
+            Flags.OPTIONAL),
     /**
      * The <code>-Xms</code> value to pass to the daemon.
      * This option takes precedence over options specified in <code>-Dmvnd.jvmArgs</code>.