feat: add marketplace metrics, privacy features, and service registry endpoints

- Add Prometheus metrics for marketplace API throughput and error rates with new dashboard panels
- Implement confidential transaction models with encryption support and access control
- Add key management system with registration, rotation, and audit logging
- Create services and registry routers for service discovery and management
- Integrate ZK proof generation for privacy-preserving receipts
- Add metrics instru

infra/helm/charts/blockchain-node/hpa.yaml

@@ -0,0 +1,64 @@
+{{- if .Values.autoscaling.enabled }}
+apiVersion: autoscaling/v2
+kind: HorizontalPodAutoscaler
+metadata:
+  name: {{ include "aitbc-blockchain-node.fullname" . }}
+  labels:
+    {{- include "aitbc-blockchain-node.labels" . | nindent 4 }}
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: {{ include "aitbc-blockchain-node.fullname" . }}
+  minReplicas: {{ .Values.autoscaling.minReplicas }}
+  maxReplicas: {{ .Values.autoscaling.maxReplicas }}
+  metrics:
+    {{- if .Values.autoscaling.targetCPUUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: cpu
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.autoscaling.targetCPUUtilizationPercentage }}
+    {{- end }}
+    {{- if .Values.autoscaling.targetMemoryUtilizationPercentage }}
+    - type: Resource
+      resource:
+        name: memory
+        target:
+          type: Utilization
+          averageUtilization: {{ .Values.autoscaling.targetMemoryUtilizationPercentage }}
+    {{- end }}
+    # Custom metrics for blockchain-specific scaling
+    - type: External
+      external:
+        metric:
+          name: blockchain_transaction_queue_depth
+        target:
+          type: AverageValue
+          averageValue: "100"
+    - type: External
+      external:
+        metric:
+          name: blockchain_pending_transactions
+        target:
+          type: AverageValue
+          averageValue: "500"
+  behavior:
+    scaleDown:
+      stabilizationWindowSeconds: 600  # Longer stabilization for blockchain
+      policies:
+      - type: Percent
+        value: 5
+        periodSeconds: 60
+    scaleUp:
+      stabilizationWindowSeconds: 60
+      policies:
+      - type: Percent
+        value: 50
+        periodSeconds: 60
+      - type: Pods
+        value: 2
+        periodSeconds: 60
+      selectPolicy: Max
+{{- end }}