Add Helm/Kubernetes runtime provider (Chart.yaml / k8s manifests)

[erdembas]

Context

Many developers work with local Kubernetes clusters (minikube, kind, k3d). Detecting Helm charts and k8s manifests would let RunHQ suggest helm install or kubectl apply commands.

What to do

1. Implement RuntimeProvider for HelmProvider in crates/runhq-core/src/scanner.rs
2. Detect Chart.yaml for Helm charts
3. Suggest helm install <chart> . and helm template .
4. Register in the providers() list
5. Add unit tests

Reference

See DockerProvider for a similar infrastructure-type provider pattern.

Acceptance

• cargo test -p runhq-core passes
• A Helm chart directory is correctly detected