feat(skill-development): add examples directory with skill templates (#43)

## Description

Add examples/ directory to the skill-development skill, making it
consistent with all other plugin-dev skills. The skill now "practices
what it preaches" by providing working skill templates that users can
copy.

## Type of Change

- [ ] Bug fix (non-breaking change that fixes an issue)
- [x] New feature (non-breaking change that adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [x] Documentation update (improvements to README, CLAUDE.md, or
component docs)
- [ ] Refactoring (code change that neither fixes a bug nor adds a
feature)
- [ ] Configuration change (changes to .markdownlint.json, plugin.json,
etc.)

## Component(s) Affected

- [ ] Commands (`/plugin-dev:*`)
- [x] Skills (methodology and best practices)
- [ ] Agents (requirements-assistant)
- [ ] Hooks (UserPromptSubmit)
- [ ] Documentation (README.md, CLAUDE.md, SECURITY.md)
- [ ] Configuration (.markdownlint.json, plugin.json, marketplace.json)
- [ ] Issue/PR templates
- [ ] Other (please specify):

## Motivation and Context

The skill-development skill was the **only** skill in plugin-dev without
an `examples/` directory. This was inconsistent since:
1. All other skills have examples/
2. The skill teaches "Provide working examples" as a best practice but
didn't follow its own guidance
3. New skill creators had to piece together examples from other skills

Fixes #40

## How Has This Been Tested?

**Test Configuration**:
- Claude Code version: latest
- GitHub CLI version: 2.63.2
- OS: macOS (Darwin 25.1.0)

**Test Steps**:
1. Verified markdownlint passes on all new files
2. Verified examples follow documented best practices (third-person
description, imperative body)
3. Confirmed SKILL.md references new examples correctly

## Checklist

### General

- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my own code
- [x] I have commented my code, particularly in hard-to-understand areas
(if applicable)
- [x] My changes generate no new warnings or errors

### Documentation

- [x] I have updated the documentation accordingly (README.md,
CLAUDE.md, or component docs)
- [x] I have updated YAML frontmatter (if applicable)
- [x] I have verified all links work correctly

### Markdown

- [x] I have run `markdownlint` and fixed all issues
- [x] My markdown follows the repository style (ATX headers, dash lists,
fenced code blocks)
- [x] I have verified special HTML elements are properly closed
(`<example>`, `<commentary>`, etc.)

### Component-Specific Checks

#### Skills (if applicable)

- [x] Description uses third-person with specific trigger phrases
- [x] SKILL.md is under 2,000 words (progressive disclosure)
- [x] Detailed content is in `references/` subdirectory
- [x] Templates follow the established format

### Testing

- [x] I have tested the plugin locally with `cc --plugin-dir
plugins/plugin-dev`
- [x] I have tested the full workflow (if applicable)
- [ ] I have verified GitHub CLI integration works (if applicable) - N/A
- [ ] I have tested in a clean repository (not my development repo) -
N/A

## Changes

### New Files

- `examples/minimal-skill.md` - Bare-bones skill template (git
conventions example)
- `examples/complete-skill.md` - Full skill with references/, examples/,
scripts/ (API testing example)
- `examples/frontmatter-templates.md` - Copy-paste frontmatter templates
for common patterns

### Modified Files

- `SKILL.md` - Added "Example Skills" section under Additional Resources

## Additional Notes

Examples follow the documentation-style pattern used by other skills
(e.g., plugin-structure/examples/minimal-plugin.md), where each example
is a markdown file that documents the skill structure with embedded code
blocks, rather than actual nested directories.

---
🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude <noreply@anthropic.com>

Author: sjnims

plugins/plugin-dev/skills/skill-development/SKILL.md

@@ -285,6 +285,14 @@ Good for: Complex domains with validation utilities
 
 ## Additional Resources
 
+### Example Skills
+
+Copy-paste ready skill templates in `examples/`:
+
+- **`examples/minimal-skill.md`** - Bare-bones skill with just SKILL.md (git conventions example)
+- **`examples/complete-skill.md`** - Full skill with references/, examples/, and scripts/ (API testing example)
+- **`examples/frontmatter-templates.md`** - Quick-reference frontmatter patterns for common use cases
+
 ### Reference Files
 
 For detailed guidance, consult: