Provide mechanism for managing resources across engines and executions

[YongGoose]

Resolves #2816

Overview

• Designing a class to manage context at the platform level
• Adding a session-level store to LauncherSession
• Adding a request-level store to Launcher
• Exposing the request-level store in EngineDiscoveryRequest and TestPlan
• Utilizing the request-level store in JupiterEngineExtensionContext

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Definition of Done

• There are no TODOs left in the code
• Method preconditions are checked and documented in the method's Javadoc
• Coding conventions (e.g. for logging) have been followed
• Change is covered by automated tests including corner cases, errors, and exception handling
• Public API has Javadoc and @API annotations
• Change is documented in the User Guide and Release Notes

[YongGoose]

What's the use case for this method? Test engines don't have access to the Launcher so we'll need to pass this store as part of LauncherDiscoveryRequest and ExecutionRequest, don't we?

I’ve drafted an initial version 02ef45b , but I think there’s still a lot of room for improvement.
If you could point out any mistakes I’ve made, I’ll make sure to fix them right away.

Even though I’ve been studying, I find it quite challenging.

PS. While resolving a git conflict, I accidentally included the commit history from the main branch, So i create a new PR 😁

[YongGoose]

@marcphilipp

I think you must be very busy with the release of version 5.12 M1.
Please feel free to leave your comments whenever it’s convenient for you.

[YongGoose]

@marcphilipp

This PR is something I’ve personally been eager to work on for a long time.
However, I still don’t have a clear sense of how to proceed with it.

If this feature gets added to JUnit 5, it would be a huge learning opportunity for me and a great addition to my skill set.
That said, I don’t want to cause any fatigue for the JUnit team—especially you, Marc.

So if you feel that I’m not quite ready to take on this PR yet, please let me know, and I’ll close it.
Either way, I’ll keep looking for other issues and do my best to contribute! 🙂

But if you’re willing to let me see it through, I’ll do my best as always.
I’ll likely need more guidance than usual compared to other tasks.