feat: support Java 25 main methods

[ML-Marco]

Fixes #4431

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[gemini-code-assist]

Summary of Changes

Hello @ML-Marco, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces support for Java 25's flexible main method definitions, allowing the MainClassFinder to correctly identify entry points in applications compiled with the latest Java versions. This enhancement ensures compatibility and proper functionality for projects leveraging JEP 512.

Highlights

• Support for Java 25 Flexible Main Methods: The MainClassFinder has been updated to recognize the new flexible main method signatures introduced in Java 25 (JEP 512), including static/instance methods with or without String[] args parameters, and with public, protected, or package-private access.
• ASM Dependency Update: The ASM library dependency has been upgraded from version 9.8 to 9.9, which is necessary to correctly parse Java 25 bytecode.
• Expanded Test Coverage: New unit tests have been added to validate the correct detection of various Java 25 flexible main method patterns and to ensure private main methods are still not recognized.

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[gemini-code-assist]

Code Review

This pull request adds support for flexible main methods as introduced in Java 25 (JEP 512). The changes involve updating the ASM dependency, modifying the main class detection logic to recognize new main method signatures for Java 25+ class files, and adding corresponding unit tests.

My review has identified a bug in the detection logic where synchronized and strictfp main methods would not be correctly identified. I've also suggested refactoring the new tests to reduce code duplication and adding more test cases for completeness. Overall, this is a great feature addition.