feat(kube): allow mutating kubectl when write permissions enabled

[mayankpande88]

Problem

kubectl_command_executor enforced a read-only verb allowlist unconditionally. On installs that grant the runner write RBAC (runner.enableWritePermissions: true), mutating commands were still rejected:

err: kubectl: verb "scale" not in read-only allowlist; mutating actions go through pkg/mutate
err: kubectl: verb "patch" not in read-only allowlist; ...
err: kubectl: verb "set" not in read-only allowlist; ...
err: kubectl: verb "-n" not in read-only allowlist; ...   # ← also a parsing bug

The legacy robusta executor ran these via KUBECTL_ALLOW_CRUD (defaulted on); the Go rewrite made the allowlist a hard gate with no escape hatch.

Changes

• Write mode gated on runner.enableWritePermissions. New KUBECTL_ALLOW_WRITE env, emitted by the chart from the same flag that grants the write ClusterRole — so the runner allowlist and cluster RBAC move together. Default false keeps kubectl strictly read-only; mutations still route to the signed pkg/mutate actions. When true, mutating verbs run and the API server's RBAC becomes the enforcement boundary.
• Fixed verb resolution past leading global flags. kubectl -n ns get pods was rejected as verb -n. firstVerb() now skips -n/--namespace/--context/-o/--kubeconfig/etc. before validating. Mutating verbs hidden behind a flag (-n default scale ...) are still caught when write mode is off.

Security posture

When write mode is on, mutating kubectl flows over the unsigned, relay-secret-gated light-action path — the same posture as the existing pod_script_run_enricher. The operator who sets enableWritePermissions: true (granting write RBAC) is explicitly opting into cluster writes. Default-off installs are unchanged and strictly read-only.

Tests

Added coverage for: reads behind global flags, rejection of mutations behind flags (no bypass), AllowWrite permitting mutations, and flags-only input. go test ./pkg/kube/ ./pkg/config/ passes; chart renders KUBECTL_ALLOW_WRITE: "false" by default.

[gemini-code-assist]

Code Review

This pull request introduces the KUBECTL_ALLOW_WRITE configuration option (gated by runner.enableWritePermissions in the Helm chart) to lift the read-only restriction on the kubectl command executor. It also adds logic to parse the actual command verb past any leading global flags. The review feedback points out that several common global flags (such as -v and --v for verbosity) are missing from the verbFlagsWithValue map, which would cause the parser to incorrectly identify their values as the command verb. It is recommended to add these missing flags and include a test case to verify this behavior.

[github-actions]

📦 Image Tags Updated

I've automatically updated the image tags in `charts/nudgebee-agent/values.yaml` to the latest versions from GHCR for the `main` branch.

The image tags are now synchronized with the latest builds and ready for release.