feat: add impediment-prioritization skill

[aj-enns]

Summary

Adds a new skill, impediment-prioritization, that ranks any list of impediments and their countermeasures using a value-stream scoring model (ROI, Cost to Implement, Ease of Deployment, Risk Factor) and a fixed prioritization formula:

Priority = ((ROI * (10 / Cost)) + (Ease * (10 / Risk))) / 2

The skill is domain-agnostic. It works with:

• GHQR / platform health-check findings
• Audit non-conformances
• Retrospective action items
• Risk registers
• Architecture review gaps
• Any free-form {impediment, countermeasure} list

It derives from value-stream-mapping practice and the A3 / lean countermeasure tradition, but is not tied to any single tool or workflow. When used inside the GitHub Enterprise / GHQR / PAK workflow, it hooks into the existing ghqr-analysis upstream and pak-report-formatting downstream; for any other workflow the ranked table is the deliverable.

What's included

• skills/impediment-prioritization/SKILL.md — method, rubric, formula, two worked examples (GitHub Enterprise and generic retrospective), guardrails.
• skills/impediment-prioritization/references/scoring-rubric.md — 1 / 5 / 10 anchor examples across four domains (Platform/DevEx, Security, SRE/Ops, App Dev/Governance) with calibration tips.
• docs/README.skills.md — regenerated to list the new skill.

Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• I have read and followed the Guidance for submissions involving paid services. (No paid services involved — the skill is tool-agnostic.)
• My contribution adds a new instruction, prompt, agent, skill, or workflow file in the correct directory. (Adds a skill under skills/impediment-prioritization/.)
• The file follows the required naming convention. (Folder and name: field are both impediment-prioritization; lowercase with hyphens; SKILL.md present; description wrapped and within 10–1024 chars.)
• The content is clearly structured and follows the example format. (Front matter + activation triggers + inputs + rubric + formula + method + output template + worked examples + guardrails + cross-references.)
• I have tested my instructions, prompt, agent, skill, or workflow with GitHub Copilot. (Validated the skill activates on prioritization / ranking requests and produces the ranked table for both GHQR-style and generic retrospective inputs.)
• I have run npm start and verified that README.md is up to date. (Ran npm run build; docs/README.skills.md regenerated to include the new entry.)
• I am targeting the staged branch for this pull request.

[github-actions]

🔍 Skill Validator Results

✅ All checks passed

Scope	Checked
Skills	1
Agents	1
Total	2
Severity	Count
---	---:
❌ Errors	0
⚠️ Warnings	0
ℹ️ Advisories	0

Summary

Level	Finding
ℹ️	Found 1 skill(s)
ℹ️	[impediment-prioritization] 📊 impediment-prioritization: 2,249 BPE tokens [chars/4: 2,256] (detailed ✓), 11 sections, 2 code blocks
ℹ️	✅ All checks passed (1 skill(s))

Full validator output

```text Found 1 skill(s) [impediment-prioritization] 📊 impediment-prioritization: 2,249 BPE tokens [chars/4: 2,256] (detailed ✓), 11 sections, 2 code blocks ✅ All checks passed (1 skill(s)) ```

[Copilot]

Pull request overview

Adds a new impediment-prioritization skill to the skills/ collection, intended to rank impediments/countermeasures using a fixed value-stream scoring rubric and prioritization formula, and registers it in the skills index docs.

Changes:

• Added skills/impediment-prioritization/SKILL.md defining activation triggers, rubric, formula, method, and worked examples.
• Added skills/impediment-prioritization/references/scoring-rubric.md with 1/5/10 anchoring examples across multiple domains.
• Updated docs/README.skills.md to include the new skill entry and reference.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
skills/impediment-prioritization/SKILL.md	New skill definition (front matter, scoring model, formula, procedure, templates/examples).
skills/impediment-prioritization/references/scoring-rubric.md	New reference rubric with anchored examples for scoring calibration.
docs/README.skills.md	Adds the skill to the generated skills list with its reference link.