Add VictoriaMetrics observability stack + sync catalog for monitoring test

- VM stack 10 charts: victoria-metrics-cluster/auth, victoria-logs-cluster,
  victoria-metrics-agent/alert, opentelemetry-collector, kube-state-metrics,
  prometheus-node-exporter, alertmanager, perses (JWT/OIDC, Infisical-ready)
- ArgoCD ApplicationSet (syncWave) + per-chart dip-values overlays
- doc/victoria-metrics-architecture.md, define-chart-resources updates
- includes pending working-tree changes (mlflow, kubeflow, apisix, CLAUDE.md)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

manifests/helm/alertmanager/1.37.0/templates/ingress.yaml

@@ -0,0 +1,47 @@
+{{- if .Values.ingress.enabled }}
+{{- $fullName := include "alertmanager.fullname" . }}
+{{- $svcPort := .Values.service.port }}
+apiVersion: {{ include "alertmanager.ingress.apiVersion" . }}
+kind: Ingress
+metadata:
+  name: {{ $fullName }}
+  labels:
+    {{- include "alertmanager.labels" . | nindent 4 }}
+    {{- if .Values.ingress.labels }}
+    {{- toYaml .Values.ingress.labels | nindent 4 }}
+    {{- end }}
+  {{- with .Values.ingress.annotations }}
+  annotations:
+    {{- toYaml . | nindent 4 }}
+  {{- end }}
+  namespace: {{ include "alertmanager.namespace" . }}
+spec:
+  {{- if .Values.ingress.className }}
+  ingressClassName: {{ .Values.ingress.className }}
+  {{- end }}
+  {{- if .Values.ingress.tls }}
+  tls:
+    {{- range .Values.ingress.tls }}
+    - hosts:
+        {{- range .hosts }}
+        - {{ . | quote }}
+        {{- end }}
+      secretName: {{ .secretName }}
+    {{- end }}
+  {{- end }}
+  rules:
+    {{- range .Values.ingress.hosts }}
+    - host: {{ .host | quote }}
+      http:
+        paths:
+          {{- range .paths }}
+          - path: {{ .path }}
+            pathType: {{ .pathType }}
+            backend:
+              service:
+                name: {{ $fullName }}
+                port:
+                  number: {{ $svcPort }}
+          {{- end }}
+    {{- end }}
+{{- end }}