Add CI overview doc with Blossom-CI flow diagram

[dpressle]

The repo has 9 GitHub Actions workflows and 10 Jenkins jobs but no single place explaining which ones run automatically on every PR versus which require a manual /build comment, a cron schedule, or a manual Jenkins trigger. This made it hard to know what to expect when opening a PR or debugging a missing check.

Adds .ci/docs/ci-overview.md cataloging every job, its trigger, and whether it's part of automatic PR CI. Also documents that only the 6 jobs nixl-ci-dispatcher fans out to are ever part of the PR CI path — the other 4 Jenkins jobs (build-container, build-wheel- nightly, build-llm-container, test-llm-container) are standalone nightly/manual jobs.

Includes a sequence diagram of the Blossom-CI flow: /build comment -> Authorization -> Black Duck vulnerability scan -> Job-trigger -> dispatcher fan-out -> per-job GitHub PR check status.

What?

Describe what this PR is doing.

Why?

Justification for the PR. If there is an existing issue/bug, please reference it. For
bug fixes, the 'Why?' and 'What?' can be merged into a single item.

How?

It is optional, but for complex PRs, please provide information about the design,
architecture, approach, etc.

Summary by CodeRabbit

• Documentation
  • Added a CI overview guide that summarizes all automated and manual build jobs across GitHub Actions and Jenkins.
  • Included a quick-reference table for workflows and job types, plus clear notes on what runs on every pull request versus manual triggers.
  • Added step-by-step guidance for the gated CI flow, Jenkins dispatch behavior, standalone jobs, and manual triggering instructions.

[github-actions]

👋 Hi dpressle! Thank you for contributing to ai-dynamo/nixl.

Your PR reviewers will review your contribution then trigger the CI to test your changes.

🚀

[coderabbitai]

📝 Walkthrough

Walkthrough

Adds a new documentation file, .ci/docs/ci-overview.md, cataloging NIXL CI jobs across GitHub Actions workflows and Jenkins jobs. It describes automatic per-PR triggers versus manual/standalone jobs, includes a quick-reference table, a Blossom-CI mermaid sequence diagram, Jenkins dispatcher fan-out details, and manual triggering instructions.

Changes

CI Overview Documentation

Layer / File(s)	Summary
Intro and quick-reference table .ci/docs/ci-overview.md	Adds document title, intro, and a quick-reference table of key CI jobs/workflows with their PR-trigger behavior.
GitHub Actions workflows documentation .ci/docs/ci-overview.md	Notes that only 6 of 10 Jenkins jobs run in PR CI, and documents each GitHub Actions workflow's trigger, purpose, and PR behavior.
Blossom-CI and Jenkins dispatcher flow .ci/docs/ci-overview.md	Documents the Blossom-CI /build-gated trigger flow with a mermaid sequence diagram, plus the Jenkins dispatcher fan-out to six PR jobs and standalone Jenkins jobs.
Manual triggering and related docs .ci/docs/ci-overview.md	Adds a "How to trigger CI manually" section and a "Related docs" section linking to other CI documentation.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Sequence Diagram(s)

sequenceDiagram
  participant Contributor
  participant GitHubActions as GitHub Actions
  participant BlossomCI as Blossom-CI
  participant JenkinsDispatcher as nixl-ci-dispatcher

  Contributor->>GitHubActions: comment "/build"
  GitHubActions->>BlossomCI: trigger workflow
  BlossomCI->>BlossomCI: authorize and scan
  BlossomCI->>JenkinsDispatcher: trigger jobs
  JenkinsDispatcher->>JenkinsDispatcher: fan out to six child jobs
  JenkinsDispatcher->>GitHubActions: report per-job PR status

Loading

Related issues: None found in the provided context.

Related PRs: None found in the provided context.

Suggested labels: documentation, ci

Suggested reviewers: None found in the provided context.

🐰 A rabbit hops through pipelines deep,
Cataloging jobs while others sleep,
Blossom blooms on "/build" so bright,
Dispatcher fans to six in flight,
Now docs reveal the CI's keep.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly describes the new CI overview documentation and the Blossom-CI flow diagram.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

_{Comment @coderabbitai help to get the list of available commands.}

[coderabbitai]

Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In @.ci/docs/ci-overview.md:
- Line 21: The “Automatic on every PR?” entry for External Contributor is
misleading because this workflow only runs for forked pull requests. Update the
CI overview table row for External Contributor in ci-overview.md so the status
is conditional, using wording like “No (fork PRs only)” or “Conditional (fork
PRs only)”, and keep the description aligned with the external_contributor
workflow and its pull_request_target trigger.
- Around line 13-14: The CI overview text is describing the trigger branch
incorrectly by implying GitHub creates the pull-request ref. Update the
documentation in the CI overview table to refer to pull-request/<n> as the
internal mirrored branch used by CI, and keep the trigger description aligned
with the workflow push events on main and the mirrored branch. Use the existing
NVIDIA NIXL Validation and AWS NIXL Validation entries as the place to make this
wording change.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: ASSERTIVE

Plan: Enterprise

Run ID: 7795b091-e447-4d51-acbb-5dcc1c14401d

📥 Commits

Reviewing files that changed from the base of the PR and between 78985be and f890c02.

📒 Files selected for processing (1)

• .ci/docs/ci-overview.md