Add support for the central mirror

[yeikel]

Summary

This PR adds support for using the central mirror defined in settings.xml when resolving Maven Wrapper distribution downloads.

Today, the wrapper plugin only applies a configured mirror if it is defined as *. This change allows the wrapper to work correctly in those environments by honoring the central mirror as well.

What changed

• The wrapper now detects and applies a mirror configured for central in settings.xml
• If both * and central mirrors are present, the existing * behaviour remains supported

Fixes #396

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[laeubi]

It looks sane to me and like something that can help users.
Even though central is not strictly "in maven" it is on the super-pom / settings. Even if that (unlikely) ever changes having this now do not harms.

[yeikel]

It looks sane to me and like something that can help users. Even though central is not strictly "in maven" it is on the super-pom / settings. Even if that (unlikely) ever changes having this now do not harms.

Thanks for the feedback. Unfortunately, I had some linting issues that I had to push back, hopefully CI passes now

[cstamas]

Not enough

[cstamas]

Check this page "Advanced Mirror Specification" section:
https://maven.apache.org/guides/mini/guide-mirror-settings.html

MirrorOf possible values:

• * - matches central
• external:* - matches central
• external:http:* - matches central
• myrepo,central,otherrepo - matches central
• myrepo,!central,otherrepo - does NOT matches central

[laeubi]

@cstamas I think it is to much to ask to support the full range I think, of course if there are demands people can extend this more and more... so why not starting small here?

[cstamas]

My stance is that code is done wrongly. It is not (raw) settings that needs to be used, and hence, have replicate/redo all the logic. Instead, code needs to use different APIs. Will craft a PR once there.

[cstamas]

Proposed alt (and complete) solution in #399

[yeikel]

Closing in favor of #399 as the solution seems better and solves the same problem