fix: apply clientConnection QPS/burst to the manager client

[abhijeet-dhumal]

What this PR does / why we need it:
The clientConnection QPS/burst configuration is validated and defaulted but never applied to the manager's Kubernetes client.

Fixes #3431

• Extracts ApplyClientConnection() in pkg/config and calls it from main.go to wire QPS/burst onto rest.Config
• Adds the missing clientConnection block to the Helm chart ConfigMap template and values.yaml
• Adds unit and end-to-end config loading tests

Checklist:

• [Docs] No doc changes needed - existing config field, just fixing the wiring.

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[Copilot]

Pull request overview

This PR fixes a wiring gap where clientConnection QPS/burst settings (already defaulted/validated in the Configuration API) were not being applied to the controller manager’s Kubernetes rest.Config, and adds Helm chart parity plus tests to prevent regression.

Changes:

• Adds ApplyClientConnection() in pkg/config and applies it before creating the controller-runtime manager.
• Extends the Helm chart to emit clientConnection into the generated manager config.
• Adds unit tests to cover applying clientConnection to a rest.Config, including default and custom config loading.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
pkg/config/config.go	Introduces ApplyClientConnection() to apply QPS/burst onto a rest.Config.
pkg/config/config_test.go	Adds tests for ApplyClientConnection() and for load+apply behavior.
cmd/trainer-controller-manager/main.go	Wires clientConnection into the manager’s REST config before ctrl.NewManager().
charts/kubeflow-trainer/values.yaml	Adds manager.config.clientConnection values (qps/burst) with defaults.
charts/kubeflow-trainer/templates/manager/configmap.yaml	Renders clientConnection into the manager configmap template.

[robert-bell]

Thanks @abhijeet-dhumal this was a good spot.

[andreyvelich]

Thanks for the contribution! This review was performed using AI tools.