OpenAPI model name generator will attempt to write to its dependency packages (e.g. go modules)

[mengqiy]

It appears that OpenAPI model name generator attempt to generate the model name file for its dependencies (e.g. k8s.io/apimachinery/pkg/apis/meta/v1) which are considered as read-only.

This issue was not caught in https://github.com/kubernetes/kubernetes/pull/131755/files#diff-d4a8ac5bfd02de3a92233b6b6f818da8aa7da55cfb6fd770fa302547a0c5f062 because everything is in staging which is writable.

Steps to repro

Clone the sample-apiserver and run ./hack/update-codegen.sh .

$ ./hack/update-codegen.sh 
Generating deepcopy code for 3 targets
Generating defaulter code for 2 targets
Generating conversion code for 2 targets
Generating openapi code for 2 targets
2026/01/20 18:09:03 Model name code generation error: failed executing generator: some targets had errors: errors in target "k8s.io/apimachinery/pkg/api/resource": open /Users/mengqiyu/golang/pkg/mod/k8s.io/apimachinery@v0.0.0-20260116132332-7daad7080a68/pkg/api/resource/zz_generated.model_name.go: permission denied
errors in target "k8s.io/apimachinery/pkg/apis/meta/v1": open /Users/mengqiyu/golang/pkg/mod/k8s.io/apimachinery@v0.0.0-20260116132332-7daad7080a68/pkg/apis/meta/v1/zz_generated.model_name.go: permission denied
errors in target "k8s.io/apimachinery/pkg/runtime": open /Users/mengqiyu/golang/pkg/mod/k8s.io/apimachinery@v0.0.0-20260116132332-7daad7080a68/pkg/runtime/zz_generated.model_name.go: permission denied
errors in target "k8s.io/apimachinery/pkg/version": open /Users/mengqiyu/golang/pkg/mod/k8s.io/apimachinery@v0.0.0-20260116132332-7daad7080a68/pkg/version/zz_generated.model_name.go: permission denied

cc: @jpbetz @Jefftree