refactor(cli): decouple EnvSettings from pkg/kube to avoid import cycles

Move the retrying round tripper used by EnvSettings into pkg/cli so
pkg/cli no longer imports pkg/kube. This preserves retry behavior while
breaking the import edge that triggers cycles for Helm library consumers
(such as the kustomize integration described in #31965).

Signed-off-by: Sumit Solanki <sumit.solanki@ibm.com>

pkg/cli/environment.go

@@ -35,7 +35,6 @@ import (
 
 	"helm.sh/helm/v4/internal/version"
 	"helm.sh/helm/v4/pkg/helmpath"
-	"helm.sh/helm/v4/pkg/kube"
 )
 
 // defaultMaxHistory sets the maximum number of releases to 0: unlimited
@@ -134,7 +133,7 @@ func New() *EnvSettings {
 			config.Burst = env.BurstLimit
 			config.QPS = env.QPS
 			config.Wrap(func(rt http.RoundTripper) http.RoundTripper {
-				return &kube.RetryingRoundTripper{Wrapped: rt}
+				return &retryingRoundTripper{wrapped: rt}
 			})
 			config.UserAgent = version.GetUserAgent()
 			return config

pkg/cli/roundtripper.go

@@ -0,0 +1,82 @@
+/*
+Copyright The Helm Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cli
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+	"net/http"
+	"strings"
+)
+
+// retryingRoundTripper retries selected transient Kubernetes API server failures.
+// Keeping this in pkg/cli avoids importing pkg/kube from EnvSettings.
+type retryingRoundTripper struct {
+	wrapped http.RoundTripper
+}
+
+func (rt *retryingRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	return rt.roundTrip(req, 1, nil)
+}
+
+func (rt *retryingRoundTripper) roundTrip(req *http.Request, retry int, prevResp *http.Response) (*http.Response, error) {
+	if retry < 0 {
+		return prevResp, nil
+	}
+	resp, rtErr := rt.wrapped.RoundTrip(req)
+	if rtErr != nil {
+		return resp, rtErr
+	}
+	if resp.StatusCode < 500 {
+		return resp, rtErr
+	}
+	if resp.Header.Get("content-type") != "application/json" {
+		return resp, rtErr
+	}
+	b, err := io.ReadAll(resp.Body)
+	resp.Body.Close()
+	if err != nil {
+		return resp, err
+	}
+
+	var ke kubernetesError
+	r := bytes.NewReader(b)
+	err = json.NewDecoder(r).Decode(&ke)
+	r.Seek(0, io.SeekStart)
+	resp.Body = io.NopCloser(r)
+	if err != nil {
+		return resp, err
+	}
+	if ke.Code < 500 {
+		return resp, nil
+	}
+	// Matches messages like "etcdserver: leader changed"
+	if strings.HasSuffix(ke.Message, "etcdserver: leader changed") {
+		return rt.roundTrip(req, retry-1, resp)
+	}
+	// Matches messages like "rpc error: code = Unknown desc = raft proposal dropped"
+	if strings.HasSuffix(ke.Message, "raft proposal dropped") {
+		return rt.roundTrip(req, retry-1, resp)
+	}
+	return resp, nil
+}
+
+type kubernetesError struct {
+	Message string `json:"message"`
+	Code    int    `json:"code"`
+}