feat(gtm-audit): Add GTM audit skill with Notion integration

- Automated GTM container detection and validation
- DataLayer event validation against GA4 specs
- Form tracking analysis and interaction simulation
- E-commerce checkout flow analysis
- Multi-platform support (GA4, Meta, LinkedIn, Google Ads, Kakao, Naver)
- Notion database export with detailed reporting
- Korean market considerations

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

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

ourdigital-custom-skills/13-gtm-audit/setup.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+# GTM Audit Tool Setup Script
+
+echo "🔧 Setting up GTM Audit Tool..."
+
+# Check Python
+if ! command -v python3 &> /dev/null; then
+    echo "❌ Python 3 is required but not installed."
+    exit 1
+fi
+
+echo "✅ Python 3 found"
+
+# Install dependencies
+echo "📦 Installing Python dependencies..."
+pip install -r requirements.txt
+
+# Install Playwright browsers
+echo "🌐 Installing Playwright browsers..."
+playwright install chromium
+
+echo ""
+echo "✅ Setup complete!"
+echo ""
+echo "Usage:"
+echo "  python gtm_audit.py --url 'https://example.com' --journey full"
+echo ""
+echo "For Claude Code:"
+echo "  claude"
+echo "  > Run a GTM audit on https://example.com"