Support changing from a constructor to a factory method in ChangeMethodTargetToStatic

[timtebeek]

Summary

• Fixes Support changing from a constructor to a factory method in ChangeMethodTargetToStatic #1804

ChangeMethodTargetToStatic now handles <constructor> method patterns by adding a visitNewClass override that converts matched new Foo(args) calls into TargetType.Foo(args) static method invocations. The constructor's simple class name becomes the initial method name, so users chain ChangeMethodName to get the final name (e.g., getLogger). Anonymous class instantiations and inner class constructors are skipped. The visitor base class was changed from JavaIsoVisitor to JavaVisitor to allow returning J.MethodInvocation from visitNewClass.

Test plan

• constructorToStaticMethod — full chain with ChangeMethodName matching the issue's use case
• constructorToStaticMethodWithReturnType — verifies the returnType option works
• constructorWithAnonymousBodyNotChanged — anonymous class bodies left unchanged
• All existing ChangeMethodTargetToStaticTest tests still pass