[2.15.2] Fix skill spec compliance across all skills

Fixed issues flagged by skill-creator spec:
- Reference files now use proper markdown links instead of backtick text
- Descriptions use third person ("This skill should be used when...")
- Added Skill Compliance Checklist to CLAUDE.md with validation commands

Affected skills: agent-native-architecture, andrew-kane-gem-writer,
compound-docs, create-agent-skills, dhh-rails-style, dhh-ruby-style,
dspy-ruby, every-style-editor, file-todos, frontend-design, gemini-imagegen

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugins/compound-engineering/skills/compound-docs/SKILL.md

@@ -150,7 +150,7 @@ Format: `[sanitized-symptom]-[module]-[YYYYMMDD].md`
 <validation_gate name="yaml-schema" blocking="true">
 
 **Validate against schema:**
-Load `schema.yaml` and classify the problem against the enum values defined in `references/yaml-schema.md`. Ensure all required fields are present and match allowed values exactly.
+Load `schema.yaml` and classify the problem against the enum values defined in [yaml-schema.md](./references/yaml-schema.md). Ensure all required fields are present and match allowed values exactly.
 
 **BLOCK if validation fails:**
 
@@ -173,7 +173,7 @@ Please provide corrected values.
 <step number="6" required="true" depends_on="5">
 ### Step 6: Create Documentation
 
-**Determine category from problem_type:** Use the category mapping defined in `references/yaml-schema.md` (lines 49-61).
+**Determine category from problem_type:** Use the category mapping defined in [yaml-schema.md](./references/yaml-schema.md) (lines 49-61).
 
 **Create documentation file:**