Gradle wrapper

//tools/gradle:gradle-wrapper runs the pinned Gradle distribution from third_party/net_gradle_gradle with the Java runtime selected by the existing rules_java toolchain. It does not download anything at run time.

bazel_agent bazel run //tools/gradle:gradle-wrapper -- --version

Gradle caches remain under ignored out/gradle/. Set GRADLE_CACHE_ROOT to redirect them for a task.