[vieiralucas]

Summary

The v0.52.0 Publish Maven Central job failed while configuring the Java SDK build, before anything was uploaded:

Could not find converter-moshi-2.11.0.jar (com.squareup.retrofit2:converter-moshi:2.11.0).
  Searched in the following locations:
    https://plugins.gradle.org/m2/com/squareup/retrofit2/converter-moshi/2.11.0/converter-moshi-2.11.0.jar

The jar answers 200 there now, so the portal miss was transient. Plugin resolution used only the plugin portal, and Gradle does not try another repository for an artifact once one has served its metadata, so adding a fallback after the portal would not help. pluginManagement now lists Maven Central first: the publish plugin's dependencies (retrofit, moshi, okhttp, ...) come from Central, and the portal serves only what it alone has, such as plugin marker artifacts.

The v0.52.0 tag is frozen; its Maven Central job is re-run separately.

Test plan

• ./gradlew --refresh-dependencies buildEnvironment resolves the plugin tree from a cold cache; compileJava passes; publishToMavenCentral is still configured.
• CI sdks Java job (./gradlew build).

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Summary by cubic

Fixes the v0.52.0 Maven Central publish job, which failed when the Gradle plugin portal served converter-moshi's POM but not its jar. pluginManagement now resolves plugin dependencies from Maven Central first and falls back to the plugin portal only for artifacts it alone has, like plugin markers. The v0.52.0 tag is frozen, so its Maven Central job is re-run separately.

^{Written for commit 1f6947a. Summary will update on new commits.}