Add ACS OPC UA Edge Server integration

[AlexGodbehere]

This PR introduces acs-opcua-server-edge, a new edge helm chart that exposes UNS topics as OPC UA tags for consumption by OPC UA clients (e.g. SCADA, HMI systems) at the edge.

What's included

New acs-opcua-server-edge edge helm chart

• Node.js OPC UA server built on node-opcua that subscribes to MQTT topics and surfaces them as OPC UA variable nodes
• Address space is built dynamically: nodes are created on the fly as new topics arrive from the MQTT broker, supporting wildcard subscriptions rather than requiring a static topic list at startup
• Last-known values are persisted to disk so the OPC UA server can serve cached values immediately on restart
• OPC UA security: supports Basic256Sha256 + SignAndEncrypt for secure username/password authentication, with SecurityPolicy.None kept available for anonymous browsing; anonymous access is configurable
• MQTT: supports optional TLS (mqtts://) with a configurable CA certificate, auto-detected from port 8883

Helm chart (edge-helm-charts/charts/opcua-server)

• Full Kubernetes deployment with configmap-driven configuration, a PVC for the value cache and PKI data, a NodePort service for external OPC UA access, and a Kerberos keytab secret
• Certificate managers use a writable /data volume (fixes node-opcua defaulting to ~/.config which is read-only in the container)
• Dynamic image tag/registry injection via %%REGISTRY%% / %%TAG%% / %%PULLPOLICY%% placeholders
• Configurable resource limits, tolerations, and host pinning

ACS service-setup integration

• Registers Local.Role.OPCUAServer (with Auth.Class.EdgeService + UNS.Group.Reader membership) and Local.Chart.OPCUAServer in the helm dump
• Adds UUIDs for the new role and chart to local-uuids.js

CI

• acs-opcua-server-edge added to the publish workflow for Docker image builds

Configuration highlights

topics:
  "UNS/v1/site/area/cell/+/Temperature": {}  # wildcard subscriptions supported

opcua:
  port: 4840
  username: "opcua"   # password auto-generated into a Secret

local:
  host: mqtt.namespace.svc.cluster.local
  port: 1883
  # tls: true         # enable for port 8883 or explicit opt-in