MavenLibraryResolver doesn't log errors

Expected behavior

Failed requests/downloads made by the MavenLibraryResolver should be logged.

Observed/Actual behavior

Failed requests/downloads made by the MavenLibraryResolver aren't logged.

Steps/models to reproduce

• Setup Paper server
• Ensure the libraries folder doesn't exist
• Install a plugin that makes use of the library loading feature. Eg: veinminer-paper-2.4.4.jar
• Make the downloads somehow fail. Eg. redirect maven central domain: echo "8.8.8.8 repo.maven.apache.org" | sudo tee -a /etc/hosts
• Start the server

You'll see a lot of messages like

[19:34:46 INFO]: [MavenLibraryResolver] Downloading https://repo.maven.apache.org...

But you won't see that they fail.

Plugin and Datapack List

> plugins
[19:41:14 INFO]: ℹ Server Plugins (1):
[19:41:14 INFO]: Paper Plugins:
[19:41:14 INFO]:  - Veinminer

Paper version

[19:25:33 INFO]: 
This server is running Paper version 1.21.4-231-ver/1.21.4@09e9afd (2025-05-19T17:59:36Z) (Implementing API version 1.21.4-R0.1-SNAPSHOT)
You are running the latest version

Other

We're a large-scale hoster and running into issues downloading artifacts from Maven Central due to their rate-limiting: https://www.sonatype.com/blog/maven-central-and-the-tragedy-of-the-commons

We initially discovered our IPs being rate-limited at another end, but ended up wondering why we don't see issues in Paper.

Not too sure about this, but it looks like Paper doesn't try to download a specific library from a specific repository. It just tries to download the required libraries from any of the provided repositories.
This may result in a lot of error messages. So, maybe just log 5XX and/or 429 responses only.

The issue names MavenLibraryResolver as the entry point; start there and reproduce the failed Maven download using the hosts-file setup described. Trace how failed requests are handled and verify that the relevant failures are logged without changing the resolver's repository behavior.