feat: Official Helm chart for gateway deployment

[initcron]

Summary

Create an official Helm chart for deploying Open MCP Gateway to Kubernetes clusters.

Parent Epic

Part of #1 - Production Kubernetes & Container Support

Helm Chart Structure

charts/mcp-gateway/
├── Chart.yaml
├── values.yaml
├── templates/
│   ├── deployment.yaml
│   ├── service.yaml
│   ├── configmap.yaml
│   ├── secret.yaml
│   ├── serviceaccount.yaml
│   ├── rbac.yaml
│   ├── ingress.yaml (optional)
│   ├── servicemonitor.yaml (optional)
│   └── networkpolicy.yaml (optional)
└── README.md

Default Values

# values.yaml
replicaCount: 1

image:
  repository: ghcr.io/agenticdevops/mcp-gateway
  tag: ""  # defaults to chart appVersion
  pullPolicy: IfNotPresent

service:
  type: ClusterIP
  port: 4444

ingress:
  enabled: false
  className: ""
  annotations: {}
  hosts:
    - host: mcp.example.com
      paths:
        - path: /
          pathType: Prefix
  tls: []

resources:
  requests:
    cpu: 100m
    memory: 128Mi
  limits:
    cpu: 500m
    memory: 512Mi

catalog:
  # Inline catalog or reference to ConfigMap
  inline: |
    servers: []
  # Or reference existing ConfigMap
  existingConfigMap: ""

gateway:
  host: "0.0.0.0"
  port: 4444
  idleTimeout: 300
  adminEnabled: true

serviceAccount:
  create: true
  name: ""
  annotations: {}

rbac:
  create: true
  # Permissions for k8s-job and k8s-service runtimes
  rules:
    - apiGroups: ["batch"]
      resources: ["jobs"]
      verbs: ["create", "delete", "get", "list", "watch"]
    - apiGroups: [""]
      resources: ["pods", "pods/log"]
      verbs: ["get", "list", "watch"]

metrics:
  enabled: true
  serviceMonitor:
    enabled: false
    interval: 30s

networkPolicy:
  enabled: false

Features

• Basic deployment with ConfigMap catalog
• ServiceAccount and RBAC for K8s runtimes
• Ingress support (nginx, traefik, etc.)
• TLS configuration
• Resource limits and requests
• Pod disruption budget
• Horizontal pod autoscaler
• ServiceMonitor for Prometheus Operator
• NetworkPolicy for security
• Multi-tenant deployment mode

Acceptance Criteria

• helm install deploys working gateway
• All configuration options documented
• Works with Helm 3.x
• Passes helm lint
• Published to artifact hub or chart repo

Installation Example

helm repo add openmcp https://agenticdevops.github.io/openmcp/charts
helm install mcp-gateway openmcp/mcp-gateway \
  --set ingress.enabled=true \
  --set ingress.hosts[0].host=mcp.example.com

References

• Helm best practices
• Artifact Hub