Add pr-dashboard skill and plugin (#1444)

* Add pr-dashboard skill and plugin

Adds a self-contained PR dashboard skill that generates and opens a
rich HTML dashboard in the browser showing GitHub pull requests for a
given date range and role filter.

- Skill: skills/pr-dashboard/ — bundles pr-dashboard-cli.mjs,
  dashboard.html, and lib/utils.mjs
- Plugin: plugins/pr-dashboard/ — makes it installable via
  `copilot skill install pr-dashboard@awesome-copilot`

Requires GitHub CLI (gh) installed and authenticated.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Restore README.instructions.md to upstream sort order

macOS locale sorts Japanese/Korean C# entries differently than Linux CI.
Restore to the upstream/staged version since we don't add any instructions.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Address PR review comments

- Fix regex character class bug: [-to]+ → (?:-|to) alternation in utils.mjs
- Fix 'last week' to return previous calendar week (Mon–Sun) not last 7 days
- Remove unused formatHumanDate and buildMarkdown exports from utils.mjs
- Fix ghApi error handling: rethrow with helpful message instead of silently
  returning parsed JSON on failure (prevents silent auth errors)
- Add pagination to searchIssues (up to 1000 results across pages)
- Add rel="noopener noreferrer" to target=_blank links in generated rows
- HTML-escape fallback template content in renderHtml to prevent injection
- Move escapeHtml to module level so it's available before renderHtml body
- Neutralise dashboard.html template: placeholder title/h1/meta/stats/tbody
- Empty __md and filename in template (CLI populates at runtime)
- Add aria-label to search input and status/review selects

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* remove newline

* Regenerate docs/README.instructions.md

* refactor(pr-dashboard): move scripts/assets per skills spec, remove plugin

- Move pr-dashboard-cli.mjs and lib/utils.mjs into scripts/ per skills spec
- Move dashboard.html into assets/ per skills spec
- Update CLI template path and SKILL.md script path reference
- Remove plugins/pr-dashboard (redundant now that gh skills install works)
- Clean up marketplace.json and docs/README.plugins.md

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

docs/README.skills.md

@@ -256,6 +256,7 @@ See [CONTRIBUTING.md](../CONTRIBUTING.md#adding-skills) for guidelines on how to
 | [power-platform-architect](../skills/power-platform-architect/SKILL.md)<br />`gh skills install github/awesome-copilot power-platform-architect` | Use this skill when the user needs to transform business requirements, use case descriptions, or meeting transcripts into a technical Power Platform solution architecture, including component selection and Mermaid.js diagrams. | None |
 | [power-platform-mcp-connector-suite](../skills/power-platform-mcp-connector-suite/SKILL.md)<br />`gh skills install github/awesome-copilot power-platform-mcp-connector-suite` | Generate complete Power Platform custom connector with MCP integration for Copilot Studio - includes schema generation, troubleshooting, and validation | None |
 | [powerbi-modeling](../skills/powerbi-modeling/SKILL.md)<br />`gh skills install github/awesome-copilot powerbi-modeling` | Power BI semantic modeling assistant for building optimized data models. Use when working with Power BI semantic models, creating measures, designing star schemas, configuring relationships, implementing RLS, or optimizing model performance. Triggers on queries about DAX calculations, table relationships, dimension/fact table design, naming conventions, model documentation, cardinality, cross-filter direction, calculation groups, and data model best practices. Always connects to the active model first using power-bi-modeling MCP tools to understand the data structure before providing guidance. | `references/MEASURES-DAX.md`<br />`references/PERFORMANCE.md`<br />`references/RELATIONSHIPS.md`<br />`references/RLS.md`<br />`references/STAR-SCHEMA.md` |
+| [pr-dashboard](../skills/pr-dashboard/SKILL.md)<br />`gh skills install github/awesome-copilot pr-dashboard` | Open a GitHub PR dashboard in the browser. Use when the user asks to see their pull requests, open the PR dashboard, show PRs for a date range, or check PR status. Trigger phrases include "show my PRs", "open PR dashboard", "pull request dashboard". | `assets/dashboard.html`<br />`scripts/lib`<br />`scripts/pr-dashboard-cli.mjs` |
 | [prd](../skills/prd/SKILL.md)<br />`gh skills install github/awesome-copilot prd` | Generate high-quality Product Requirements Documents (PRDs) for software systems and AI-powered features. Includes executive summaries, user stories, technical specifications, and risk analysis. | None |
 | [premium-frontend-ui](../skills/premium-frontend-ui/SKILL.md)<br />`gh skills install github/awesome-copilot premium-frontend-ui` | A comprehensive guide for GitHub Copilot to craft immersive, high-performance web experiences with advanced motion, typography, and architectural craftsmanship. | None |
 | [project-workflow-analysis-blueprint-generator](../skills/project-workflow-analysis-blueprint-generator/SKILL.md)<br />`gh skills install github/awesome-copilot project-workflow-analysis-blueprint-generator` | Comprehensive technology-agnostic prompt generator for documenting end-to-end application workflows. Automatically detects project architecture patterns, technology stacks, and data flow patterns to generate detailed implementation blueprints covering entry points, service layers, data access, error handling, and testing approaches across multiple technologies including .NET, Java/Spring, React, and microservices architectures. | None |