KAFKA-20857: Use Java 25 in Docker images

[lh0156]

What

Update the JVM and native Docker build images to Java 25, the latest LTS supported by Kafka.

• Use Eclipse Temurin 25 JRE Alpine for JVM image build and runtime stages.
• Use GraalVM Community 25 for native-image compilation.
• Stop the JVM used for dynamic CDS generation by its captured PID so the JSA archive is generated reliably despite long classpaths being truncated by process discovery.

Testing

• ./gradlew releaseTarGz --no-build-cache --console=plain
• JVM Docker build stage and final image build with Java 25 passed.
• JVM JSA generation exercised Kafka startup, topic creation, produce, consume, and graceful shutdown; both kafka.jsa and storage.jsa were produced.
• JVM image smoke test: kafka-topics.sh --version -> 4.4.0-SNAPSHOT.
• GraalVM Community 25 native-image build and final image build passed.
• Native image smoke test: kafka.Kafka --help.
• bash -n docker/jvm/jsa_launch docker/native/native_command.sh
• git diff --check

This change does not modify Kafka APIs, protocols, or configuration semantics, so no KIP is required.

Reviewers: Arthur S (github:arixmkii)

[arixmkii]

GraalVM community has moved to new release scheme delivering CPU only with feature releases. Current one has tag 25i2 which can be viewed in https://github.com/graalvm/container/pkgs/container/graalvm-community and is equivalent of https://github.com/graalvm/graalvm-ce-builds/releases/tag/graal-25.2.4

OpenJDK LTS support equivalent to GraalVM EE by Oracle will be only available from mandrel project https://github.com/graalvm/mandrel but they lag behind with release times and I'm not sure of they publish ready to use Docker images.

Current ghcr.io/graalvm/graalvm-community:25 is 6 months old already (missing 2 CPU releases). It is not a great option to have.

[arixmkii]

It seems Mandrel images are only published to Quay https://groups.google.com/g/quarkus-dev/c/Cs-9VKrASbI?pli=1 and are heavily leaning toward RHEL runtimes, so, it should be checked if they are suitable to be used as a replacement as is.

[lh0156]

Addressed in e348eae.

• Updated the native build image from ghcr.io/graalvm/graalvm-community:25 to 25i2, the current JDK 25.0.4 CPU-release tag available for both linux/amd64 and linux/arm64.
• Updated the native-image documentation link from the JDK 21-specific page to GraalVM's version-neutral page.
• The RED regression assertion reproduced the stale :25 tag; the GREEN assertion passes after the change, and git diff --check passes.

A local Docker build check could not resolve registry metadata because this environment lacks docker-credential-desktop; the public GHCR manifest was verified directly.