Housekeeping: consolidate label workflows, improve internal docs

[vitorvasc]

• I have read and followed the Contributing docs, especially the "First-time contributing?" section.
• This PR has content that I did not fully write myself.
  • I used AI and I have read and followed the Generative AI Contribution Policy.
• I have the experience and knowledge necessary to understand, review, and validate all content in this PR.¹

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• Split CI Workflows page from maintainer docs into separate subpages. Preview: https://deploy-preview-9578--opentelemetry.netlify.app/site/build/ci-workflows/

Footnotes

1. Yes, I can answer maintainer questions about the content of this PR, without using AI. ↩

[Copilot]

Pull request overview

This PR reorganizes the OpenTelemetry.io maintainer documentation for GitHub Actions CI workflows into subpages, and consolidates PR-labeling workflows so checks appear grouped under “Label gate / …” in the GitHub UI.

Changes:

• Consolidates PR component labeling and approval-label management into a single label-gate.yml workflow, and updates related workflow references.
• Splits the former single CI workflows documentation page into multiple subpages under content/en/site/build/ci-workflows/.
• Adds new docs pages describing the label gate system, blog publish labeling, PR fix directives, and a list of other workflows.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
content/en/site/build/ci-workflows/_index.md	Adds the CI workflows section landing page for the new doc subsection.
content/en/site/build/ci-workflows/label-gate.md	Documents the consolidated label-gating/approval-label system and its security model.
content/en/site/build/ci-workflows/blog-publish-labels.md	Documents the scheduled blog publish labeling workflow and Slack notifications.
content/en/site/build/ci-workflows/pr-fix-directives.md	Documents /fix PR comment directives and the two-stage patch pipeline.
content/en/site/build/ci-workflows/other-workflows.md	Lists additional CI workflows and their purposes.
content/en/site/build/ci-workflows.md	Removes the prior monolithic CI workflows doc page (replaced by the new subsection).
.github/workflows/pr-review-trigger.yml	Updates the “learn more” link to the new label gate docs anchor.
.github/workflows/label-prs.yml	Removes the standalone component-labeling workflow (functionality moved into label gate).
.github/workflows/label-gate.yml	Renames/reframes the workflow and adds a component-labeling job under the consolidated workflow.

Comments suppressed due to low confidence (3)

.github/workflows/label-gate.yml:36

• Security concern: the update-approval-labels job later checks out code using ref: ${{ github.event.pull_request.base.sha || github.sha }}. For workflow_run executions this falls back to github.sha, which can be the untrusted PR head SHA in the chaining pattern, meaning privileged steps could execute scripts from PR code. Ensure workflow_run always checks out a trusted ref (e.g., default branch / PR base SHA fetched via API after reading the PR number), and never the PR head.
  .github/workflows/label-gate.yml:28
• add-component-labels runs with pull-requests: write but lacks the repository-owner guard used elsewhere (e.g., update-approval-labels in this workflow, and component-owners.yml). Consider adding if: github.repository_owner == 'open-telemetry' && github.event_name == 'pull_request_target' to prevent this job from doing privileged writes when this workflow is run from forks/clones of the repo.
  content/en/site/build/ci-workflows/blog-publish-labels.md:104
• The [batch-script] link is pinned to a specific commit (blob/248cc6f/...). This will become outdated over time; prefer linking to blob/main/... unless you intentionally need to reference an immutable historical version.

[blog]:
  https://github.com/open-telemetry/opentelemetry.io/blob/main/.github/workflows/blog-publish-labels.yml
[batch-script]:
  https://github.com/open-telemetry/opentelemetry.io/blob/248cc6f/.github/scripts/blog-publish-check.sh

[Copilot]

Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Comments suppressed due to low confidence (1)

.github/workflows/label-gate.yml:3

• The “learn more” link points to /site/build/ci-workflows/#label-gate, but the CI workflow docs were moved to a dedicated subpage (/site/build/ci-workflows/label-gate/). The index page at /ci-workflows/ doesn’t define a #label-gate anchor, so this link will 404; update it to the new documentation URL.