docs(changelog): merge queue enqueue by label

[samgutentag]

Summary

• Adds changelog entry for label-based PR enqueueing (changelog/2026-05-19-merge-queue-enqueue-by-label.mdx)
• Nav files (docs.json, changelog/index.mdx, merge-queue/changelog.mdx) generated by sync-changelog.py — no manual edits

Supersedes #37, which had the same entry but with hand-edited nav files. This PR tests the automated workflow from #74.

Test plan

• changelog-check workflow passes (proves the sync script output matches)
• Mintlify preview renders the entry at /changelog and /merge-queue/changelog

🤖 Generated with Claude Code

[mintlify]

Preview deployment for your docs. Learn more about Mintlify Previews.

Project	Status	Preview	Updated (UTC)
trunk	🟢 Ready	View Preview	May 26, 2026, 10:47 PM

💡 Tip: Enable Workflows to automatically generate PRs for you.

[samgutentag]

Verification status (2026-05-26): unknown

Could not determine rollout state from available signals. Chaining to verify-docs-against-code for content-accuracy check.

• Eng PR: none found in PR body
• Linear ticket: none found in PR body
• Flag: n/a

This is a changelog entry PR with no linked eng PR or Linear ticket. To enable full verification, add a TRUNK-XXXX reference or eng PR link to the PR description.

[samgutentag]

Code verification (2026-05-26): no claim candidates found

The PR adds a changelog entry describing the "enqueue by label" feature. The content is behavioral prose (feature description, UI navigation path, example label names) with no code-level factual claims (API field names, numeric limits, endpoint paths, branch patterns, CLI flags, or environment variables) to verify against source.

No draft change or code-verification label applied.