Java25 support

[Voyinno]

Add Java 25 Support

Summary

This PR adds support for Java 25 (class file version 69) to yGuard, including:

• Accept major version 69 class files
• Handle the new ACC_IDENTITY flag (shares bit value with ACC_SUPER)
• Recognize, parse, and remap the new LoadableDescriptors attribute (preview feature)

Related Issues

Addresses issue 153

[thomasbehr]

@Voyinno Thank you very much for your effort. It seems your work is based on this preliminary list of todos. However, as far as I can tell neither ACC_IDENTITY nor LoadableDescriptors made it into Java 25 (at least I can find no mention of either the access flag or the attribute in The Java Virtual Machine Specification, Java SE 25 Edition). But maybe that is because ACC_IDENTITY and LoadableDescriptors are preview features.
Can you maybe share actual Java code snippets and the corresponding compiler commands to generate class files that use ACC_IDENTITY or LoadableDescriptors or both?