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/opentelemetry-collector/0.156.2/CONTRIBUTING.md

@@ -0,0 +1,12 @@
+# Collector Chart Contributing Guide
+
+All changes to the chart require a bump to the version in `chart.yaml`. See the [Contributing Guide](https://github.com/open-telemetry/opentelemetry-helm-charts/blob/main/CONTRIBUTING.md#versioning) for our versioning requirements.
+
+Once the chart version is bumped, the examples must be regenerated.  You can regenerate examples by running `make generate-examples CHARTS=opentelemetry-collector`.
+
+## Bumping Default Collector Version
+
+1. Increase the minor version of the chart by one and set the patch version to zero.
+2. Update the chart's `appVersion` to match the new collector version.  This version will be used as the image tag by default.
+3. Review the corresponding release notes in [Collector Core](https://github.com/open-telemetry/opentelemetry-collector/releases), [Collector Contrib](https://github.com/open-telemetry/opentelemetry-collector-contrib/releases), and [Collector Releases](https://github.com/open-telemetry/opentelemetry-collector-releases/releases).  If any changes affect the helm charts, adjust the helm chart accordingly.
+4. Run `make generate-examples CHARTS=opentelemetry-collector`.