docs(external): introduce log namespace guide

[pront]

Summary

I wrote a guide to demonstrate how log namespacing works.

Change Type

• Bug fix
• New feature
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

How did you test this PR?

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the "no-changelog" label to this PR.

Notes

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References

Ref: #22928

[jszwedko]

Just one comment, otherwise 👍

[maycmlee]

Created this docs card for editorial review: https://datadoghq.atlassian.net/browse/DOCS-10696

[datadog-vectordotdev]

Datadog Report

Branch report: pront/log-namespace-guide
Commit report: e06cd01
Test service: vector

✅ 0 Failed, 7 Passed, 0 Skipped, 25.45s Total Time

[jszwedko]

A couple of comments, otherwise 👍

[joepeeples]

Just one unclear sentence I'd recommend revising. Feel free to ping me again for a quick approval when ready!

[jszwedko]

Nit: it would have been useful to include website in the branch name to get a preview deploy 🙂

[jszwedko]

Just a couple of comments, otherwise 👍 This seems like a useful guide!

[pront]

Nit: it would have been useful to include website in the branch name to get a preview deploy 🙂

I renamed the branch which immediately closed the PR. Let's continue here: #22985