Improvements needed for external MongoDB, OpenTelemetry metrics, and ClickHouse schema support

Hi HyperDX team,

Thanks for the great work on this project. I’ve encountered a few issues and improvement opportunities while integrating HyperDX into our production Kubernetes setup:

1. External MongoDB PVC issue
When configuring HyperDX with an external MongoDB, the Helm chart still tries to create a PersistentVolumeClaim for MongoDB, even though it’s not used. This PVC is left unbound and causes noise in the cluster. Ideally, no PVC should be created if mongodb.enabled=false.

2. CPU utilization metrics deprecated in OpenTelemetry Collector
In recent versions of the OpenTelemetry Collector, the following metrics are disabled by default:

k8s.pod.cpu_utilization

k8s.container.cpu_utilization

k8s.node.cpu_utilization

They’ve been replaced with cpu.usage metrics per OpenTelemetry’s [deprecation notice](https://opentelemetry.io/blog/2025/kubeletstats-receiver-metrics-deprecation/). HyperDX should update its expectations and dashboards to reflect this change.

3. ClickHouse "Clickstack" improvements
When using an external ClickHouse instance:

The necessary schemas and users are not automatically created. This requires manual setup and breaks automation.

There should be a migration mechanism to create all required users and schemas, especially for the HyperDX app.

More importantly, there should be support for selecting engine types, including:

ReplicatedMergeTree

SharedMergeTree

Single-node MergeTree

In my case, I manually created the schemas and used Distributed tables backed by ReplicatedMergeTree, but a supported configuration would be highly valuable for ClickHouse power users.

Happy to assist with testing improvements or provide more details.

Thanks!