• Add Go + Java + Python lang-SDK coordinator system test on KubernetesExecutor

Adds a kind-based system test that runs one Dag (lang_sdk_combined) whose tasks span the Python task-runner and the Go/Java coordinators on the KubernetesExecutor. The golang/java queues route to their coordinators, each carrying a pod_template_file (the worktree-1 feature). Each worker pod's init container stages the queue's artifact (Go binary / Java jar) from a per-language localstack S3 bucket through the DagBundle interface into a shared emptyDir that is the coordinator's executables_root/jars_root. The Go queue runs on the prod image (self-contained static binary); the Java queue runs on the CI image (bundles the JVM the JavaCoordinator needs).

New k8s-test-only bundles: go-sdk/example/k8s_combined and java-sdk/k8s-example. Provisioning is a new breeze command, breeze k8s setup-lang-sdk-test, which builds the artifacts, deploys localstack, uploads artifacts and the Python stub Dag, renders the pod-template image placeholders, and installs the Helm release.

• Wire up lang-sdk test with breeze k8s command

• Keep the dags-folder bundle when provisioning the lang-SDK k8s test

The lang-SDK Helm values set config.dag_processor.dag_bundle_config_list to only the localstack S3 bundle, which replaced the default dags-folder bundle. The standard KubernetesExecutor example-Dag tests share the same test run, so dropping dags-folder marked their Dags stale and their dagRun triggers returned
404. Configure the bundles additively via dagProcessor.dagBundleConfigList (the chart-recommended input) so both the example Dags and the lang-SDK stub Dag are served.

• Move lang-SDK k8s example sources out of go-sdk/java-sdk into kubernetes-tests

The Go and Java coordinator example sources for the KubernetesExecutor lang-SDK system test lived under go-sdk/example/k8s_combined and java-sdk/k8s-example, cluttering the SDK source trees. Move them next to the rest of the test assets under kubernetes-tests/lang_sdk/ (go_example, java_example).

go_example becomes its own Go module resolving the in-repo go-sdk via a replace directive (it no longer sits inside the go-sdk module); java_example stays a standalone Gradle build that resolves the SDK from mavenLocal, now built with java-sdk's gradle wrapper pointed at the moved project. The breeze provisioning command, README, and stub-Dag docs are updated to the new paths. # Conflicts:

dev/breeze/doc/images/output_setup_check-all-params-in-groups.txt # dev/breeze/doc/images/output_setup_regenerate-command-images.txt

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