[GRADLE-WRAPPER] Worker isolation log visiblity update & documentation fix

[xsveda]

wrokerIsolation property status message always appears in the build output. This pollutes the log significantly in builds when a multiple standalone specs are to be processed. Our current projects generates over 130 individual open api specs. Similar to #11211 where more such scenarios are described.

CC: @Picazsoo

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---

Summary by cubic

Suppress worker isolation status logs when Gradle runs with --quiet to reduce build noise in projects with many specs. Update the Gradle plugin README to correctly document classloader as the default workerIsolation.

^{Written for commit 39d2e2b. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 2 files

_{Re-trigger cubic}

[Picazsoo]

Hello @xsveda, thanks for raising this issue and providing the PR.

I understand the reasoning for moving the message to info, but I worry it becomes too hard to discover. The workerIsolation parameter is a fairly new/obscure option. When set incorrectly it either increases memory pressure or slows down generation (by starting separate JVM per task), so the user should be able to pick their preferred trade-off. I presume this message is the main way users learn the parameter exists and how to switch modes. At info it only shows with --info (verbose and global), so most people would never see it.

Since #23831 added a quiet flag, could we gate the message behind that instead of lowering the log level? It stays visible by default (keeping the hint discoverable) while still giving a clean way to silence it, and it stays consistent with the banner suppression. Something like:

if (quiet.getOrElse(false) != true) {
    logger.lifecycle("[openApiGenerate] Worker isolation: ...")
}

on both branches. The quiet property is already wired in, so it should be a small change. What do you think?

For context: when I updated the Gradle plugin to support the modern worker features, I added this isolation choice precisely because the wrong mode had bitten me before, so I'd really like to keep it visible rather than tucked away behind --info.

[xsveda]

Thank you @Picazsoo for the hint, I did not realise the quiet mode flag is already available in this context.

I agree, this is much better approach 👍

[Picazsoo]

But to think of it, the obnoxious workerIsolation message could also announce the possibility of using the quiet flag 🤔.

[Picazsoo]

Hi @xsveda this failure isn't related to your changes. The openapi-generator-gradle-plugin-mvn-wrapper job failed on a transient network error while downloading the Gradle distribution:

Could not install Gradle distribution from 'https://services.gradle.org/distributions/gradle-8.14.4-bin.zip'

Just revert and reapply your last commit, then push to retrigger the tests:

That should get CI to run again and it will hopefully pass.

This is how I do it.