Create new OTel Correlation Guide

[brett0000FF]

What does this PR do? What is the motivation?

• Existing content was outdated and fragmented.
• This change unifies all correlation content into a single guide.

Fixes:

• Logs info was outdated--customers should use trace_id now.
• DBM correlation info was missing.
• Unified Service Tagging info was missing.
• Unifies correlating traces, metrics, logs, RUM, and DBM into a single guide.

TODOs:

• Remove singular guides and content reuse.
• Add aliases for removed content.
• Link to this new guide from specific doc areas.
• Add caveat for non-DDOT Collector support if trace_id isn't supported yet.

Merge instructions

Merge readiness:

• Ready for merge

For Datadog employees:

Your branch name MUST follow the <name>/<description> convention and include the forward slash (/). Without this format, your pull request will not pass CI, the GitLab pipeline will not run, and you won't get a branch preview. Getting a branch preview makes it easier for us to check any issues with your PR, such as broken links.

If your branch doesn't follow this format, rename it or create a new branch and PR.

[6/5/2025] Merge queue has been disabled on the documentation repo. If you have write access to the repo, the PR has been reviewed by a Documentation team member, and all of the required checks have passed, you can use the Squash and Merge button to merge the PR. If you don't have write access, or you need help, reach out in the #documentation channel in Slack.

Additional notes

[github-actions]

📝 Documentation Team Review Required

This pull request requires approval from the @DataDog/documentation team before it can be merged.

Please ensure your changes follow our documentation guidelines and wait for a team member to review and approve your changes.

[github-actions]

Preview links (active after the build_preview check completes)

Modified Files

• https://docs-staging.datadoghq.com/brett.blue/otel-correlation/opentelemetry/correlate/