[WIP] Migrate java-exception-stacktraces to JUnit 6

[Copilot]

Migration Plan: java-exception-stacktraces to JUnit 6

• Understand current configuration (JUnit 5.13.4, Surefire 2.19.1)
• Update Maven Surefire plugin from 2.19.1 to 3.5.4
• Remove junit-platform-surefire-provider dependency (not needed with Surefire 3.x)
• Update JUnit Jupiter dependency from 5.13.4 to 6.0.1
• Change from junit-jupiter-engine to junit-jupiter artifact
• Add junit-bom for dependency management
• Verify the project builds successfully
• Run tests to ensure everything works correctly

Original prompt

Migrate java-exception-stacktraces to JUnit 6

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