[workshop-diagrams] Add theme-aware explanatory diagram for PR reviewer agent and skill split

[github-actions]

Summary

This PR adds a new conceptual explanatory diagram to workshop/14b-pr-reviewer-workflow.md illustrating the three-part agent/skill split that is the core concept of that step.

Changes

Workshop file changed: workshop/14b-pr-reviewer-workflow.md

Change type: New concept diagram (no existing image to migrate)

SVG files added:

• workshop/images/14b-agent-skill-split-light.svg — light-theme variant
• workshop/images/14b-agent-skill-split-dark.svg — dark-theme variant

Why this diagram helps learners

The step introduces a three-layer architecture (Parent Brief → pr-reviewer agent + pr-review-standards skill → Safe Output) explained only in prose and a table. The diagram makes the runtime flow visible at a glance:

1. PR Event fires the workflow
2. Parent Brief orchestrates (layer 1 — coordinate)
3. pr-reviewer agent investigates the diff and applies the skill (layer 2 — investigate, reusable)
4. pr-review-standards skill defines quality criteria (embedded in layer 2)
5. Safe Output submit-pull-request-review performs the controlled write (layer 3)

Learners can immediately see why updating the skill does not require changing the agent, and vice versa — the key insight the text tries to convey.

Quality checks

• scripts/check-svg-visual-language.js: 0 violations
• Markdownlint: 0 issues
• Both SVGs: 1200x560 canvas, theme-appropriate palettes, role=img, aria-label, data-visual-kind=diagram, data-visual-id, data-node, no gradients
• picture block uses canonical theme-aware format with light variant as fallback

Warning

Firewall blocked 6 domains

The following domains were blocked by the firewall during workflow execution:

• accounts.google.com
• awmgmcpg
• clients2.google.com
• redirector.gvt1.com
• update.googleapis.com
• www.google.com

To allow these domains, add them to the network.allowed list in your workflow frontmatter:

network:
  allowed:
    - defaults
    - "accounts.google.com"
    - "awmgmcpg"
    - "clients2.google.com"
    - "redirector.gvt1.com"
    - "update.googleapis.com"
    - "www.google.com"

See Network Configuration for more information.

Generated by 🧠 Workshop Explanatory Diagram Generator · 165.3 AIC · ⌖ 9.37 AIC · ⊞ 6.8K · ◷

• expires on Aug 15, 2026, 5:32 AM UTC