docs: add troubleshooting step for clickhouse and aquasec (#628)

## Overview
Update langsmith self hosted documentation with a troubleshooting guide
when running in environments with AquaSec.

## Type of change

**Type:** [Replace with: New documentation page / Update existing
documentation / Fix typo/bug/link/formatting / Remove outdated content /
Other]

## Related issues/PRs
<!-- 
Link to related issues, feature PRs, or discussions (if applicable)

To automatically close an issue when this PR is merged, use closing
keywords:
- "closes #123" or "fixes #123" or "resolves #123"

For regular references without auto-closing, just use:
- "#123" or "See issue #123"

Examples:
- closes #456 (will auto-close issue #456 when PR is merged)
- See #789 for context (will reference but not auto-close issue #789)
-->
- GitHub issue:
- Feature PR:

<!-- For LangChain employees, if applicable: -->
- Linear issue:
- Slack thread:

## Checklist
<!-- Put an 'x' in all boxes that apply -->
- [ ] I have read the [contributing guidelines](README.md)
- [ ] I have tested my changes locally using `docs dev`
- [ ] All code examples have been tested and work correctly
- [ ] I have used **root relative** paths for internal links
- [ ] I have updated navigation in `src/docs.json` if needed
- I have gotten approval from the relevant reviewers
- (Internal team members only / optional) I have created a preview
deployment using the [Create Preview Branch
workflow](https://github.com/langchain-ai/docs/actions/workflows/create-preview-branch.yml)

## Additional notes
<!-- Any other information that would be helpful for reviewers -->

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Kathryn May <44557882+katmayb@users.noreply.github.com>

Author: 3 people

src/langsmith/troubleshooting.mdx

@@ -176,3 +176,30 @@ langchain-clickhouse:
 docker compose down --volumes
 docker compose up
 ```
+
+### *ClickHouse fails to start up when running a cluster with AquaSec*
+
+In some environments, AquaSec may prevent ClickHouse from starting up correctly. This may manifest as the ClickHouse pod not emitting any logs and failing to get marked as ready.
+Generally this is due to `LD_PRELOAD` being set by AquaSec, which interferes with ClickHouse. To resolve this, you can add the following environment variable to your ClickHouse deployment:
+
+#### Kubernetes
+
+Edit your `langsmith_config.yaml` (or corresponding config file) and set the `AQUA_SKIP_LD_PRELOAD` environment variable:
+
+```yaml
+clickhouse:
+  statefulSet:
+    extraEnv:
+      - name: AQUA_SKIP_LD_PRELOAD
+        value: "true"
+```
+
+#### Docker
+
+Edit your `docker-compose.yaml` and set the `AQUA_SKIP_LD_PRELOAD` environment variable:
+
+```yaml
+langchain-clickhouse:
+  environment:
+    - AQUA_SKIP_LD_PRELOAD=true
+```