refactor(skills): Restructure skills to dual-platform architecture

Major refactoring of ourdigital-custom-skills with new numbering system:

## Structure Changes
- Each skill now has code/ (Claude Code) and desktop/ (Claude Desktop) versions
- New progressive numbering: 01-09 General, 10-19 SEO, 20-29 GTM, 30-39 OurDigital, 40-49 Jamie

## Skill Reorganization
- 01-notion-organizer (from 02)
- 10-18: SEO tools split into focused skills (technical, on-page, local, schema, vitals, gsc, gateway)
- 20-21: GTM audit and manager
- 30-32: OurDigital designer, research, presentation
- 40-41: Jamie brand editor and audit

## New Files
- .claude/commands/: Slash command definitions for all skills
- CLAUDE.md: Updated with new skill structure documentation
- REFACTORING_PLAN.md: Migration documentation
- COMPATIBILITY_REPORT.md, SKILLS_COMPARISON.md: Analysis docs

## Removed
- Old skill directories (02-05, 10-14, 20-21 old numbering)
- Consolidated into new structure with _archive/ for reference

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

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

.claude/commands/gtm-audit.md

@@ -0,0 +1,42 @@
+# GTM Audit
+
+Lightweight Google Tag Manager audit tool.
+
+## Triggers
+- "audit GTM", "check dataLayer", "GTM 검사"
+
+## Capabilities
+
+1. **Container Analysis** - Tags, triggers, variables inventory
+2. **DataLayer Validation** - Check event structure
+3. **Form Tracking** - Verify form submission events
+4. **E-commerce Check** - Validate purchase/cart events
+
+## Scripts
+
+```bash
+# Audit GTM container
+python ourdigital-custom-skills/20-gtm-audit/code/scripts/gtm_audit.py \
+  --url https://example.com
+
+# With detailed dataLayer check
+python ourdigital-custom-skills/20-gtm-audit/code/scripts/gtm_audit.py \
+  --url https://example.com --check-datalayer --output report.json
+```
+
+## Audit Checklist
+
+### Container Health
+- [ ] GTM container loads correctly
+- [ ] No JavaScript errors from GTM
+- [ ] Container ID matches expected
+
+### DataLayer Events
+- [ ] `page_view` fires on all pages
+- [ ] `purchase` event has required fields
+- [ ] Form submissions tracked
+
+### Common Issues
+- Missing ecommerce object
+- Incorrect event names (GA4 format)
+- Duplicate event firing