Add Java 11 Nestmate support to java.lang.Class model

[HritikRaj2]

Summary

Implemented missing Java 11 Nestmate access control methods in the java.lang.Class model. This allows JPF to execute code that relies on getNestHost() and isNestmateOf(), which are increasingly common in modern Java libraries.

Changes

• Modified: src/classes/modules/java.base/java/lang/Class.java
  • Added getNestHost(): Traversing getEnclosingClass() to find the nest host (top-level class).
  • Added isNestmateOf(Class): Compares nest hosts of two classes.
• Added: src/tests/gov/nasa/jpf/test/java/lang/NestmateTest.java
  • Verified behavior for Top-Level classes (host is self).
  • Verified behavior for Inner classes (host is enclosing class).

Testing

• NestmateTest.java passes
• Full build successful.

Relation to Issues

Partial fix for general "Missing Methods in Class" issues (like #235), specifically targeting Java 11 support.

[HritikRaj2]

Hi @cyrille-artho, following your advice to focus on functionality rather than test optimization, I've submitted a PR adding Java 11 Nestmate support (getNestHost, isNestmateOf) to the Class model.

I included a new unit test to verify the behavior for both top-level and inner classes. Ready for your review!

[cyrille-artho]

Thank you for this addition. The implementation looks correct, and a few more tests against unusual cases can ascertain that.
Please remove the extensive formatting changes at the beginning, as this increases the size of the patch and may make it hard to merge to other branches later.

[cyrille-artho]

Please try not to reformat existing code/comments, as this can make it harder to merge your patch into other branches later.

[cyrille-artho]

Looks good. Please also add a test for some other cases: "If this Class object represents a primitive type, an array type, or void, then this method returns this".

[HritikRaj2]

Thanks for the review, @cyrille-artho! I have reverted the formatting changes to the license header to keep the diff clean. I also added the requested test cases for primitives, arrays, and void in NestmateTest.java. Ready for another look!