Restructure skill numbering: SEO 11-30, GTM 60-69, reserve 19-28 for future skills

Renumber 12 existing skills to new ranges:
- SEO: 11→13, 12→18, 13→16, 14→17, 15→14, 16→15, 17→29, 18→30, 19→12
- GTM: 20→60, 21→61, 22→62

Update cross-references in gateway architect/builder skills, GTM guardian
README, CLAUDE.md (skill tables + directory layout), and AGENTS.md
(domain routing ranges).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

custom-skills/62-gtm-guardian/desktop/references/sgtm-guide.md

@@ -0,0 +1,113 @@
+# Server-side GTM Guide
+
+sGTM 아키텍처 옵션 및 설정 가이드.
+
+## Why Server-side GTM?
+
+| Benefit | Description |
+|---------|-------------|
+| Data Control | 클라이언트 → 서버 → 벤더 흐름 제어 |
+| Privacy | PII 필터링, 서버에서 처리 |
+| Cookie Duration | 1st-party cookie (최대 2년) |
+| Performance | 클라이언트 JS 감소 |
+| Reliability | Ad blocker 영향 최소화 |
+
+## Architecture Options
+
+### Option 1: GCP Cloud Run
+```
+Browser → Your Domain (1st-party) → GCP Cloud Run → GA4/Ads/Meta
+```
+- **Pros**: 완전한 제어, GCP 통합
+- **Cons**: GCP 전문 지식 필요
+- **Cost**: Low ~$20, Medium ~$100, High $200+/월
+
+### Option 2: Stape.io (Managed)
+```
+Browser → Stape CDN → Stape Server → GA4/Ads/Meta
+```
+- **Pros**: 간편 설정 (10분), 관리형, 한국 리전
+- **Cons**: 월정액, 벤더 종속
+- **Cost**: Starter $20, Business $50, Scale $150/월
+
+### Option 3: Google Tag Gateway
+```
+Browser → Google Gateway → Google Cloud (Managed) → GA4/Ads
+```
+- **Pros**: Google 관리형, 무료(제한적)
+- **Cons**: Google 태그만 지원, 제한된 커스터마이징
+
+## Selection Guide
+
+| Requirement | Recommendation |
+|-------------|----------------|
+| Google 태그만 | Tag Gateway |
+| 빠른 구현 | Stape.io |
+| 완전한 제어 | GCP Cloud Run |
+| Third-party 태그 (Meta 등) | Stape 또는 GCP |
+
+## Client Configuration
+
+### Web Container 설정
+```javascript
+gtag('config', 'G-XXXXXXXXXX', {
+  'server_container_url': 'https://gtm.yourdomain.com'
+});
+```
+
+### GTM GA4 Configuration Tag
+```
+Advanced Settings:
+  Server container URL: https://gtm.yourdomain.com
+```
+
+## Stape Quick Setup
+
+1. **계정 생성**: stape.io
+2. **Container 생성**: Region = Seoul (asia-northeast3)
+3. **Custom Domain 연결**
+   ```
+   DNS: gtm.example.com CNAME [stape-provided-address]
+   ```
+4. **GTM Server Container ID 연결**
+5. **Web Container 수정**: server_container_url 추가
+
+## Server Tags
+
+### GA4 Tag
+```
+Measurement ID: G-XXXXXXXXXX
+Event Name: {{Event Name}}
+Event Parameters: {{Event Data}}
+```
+
+### Google Ads Conversion
+```
+Conversion ID: AW-XXXXXXXXX
+Conversion Label: [Label]
+Enhanced Conversions: Enabled
+```
+
+### Meta Conversions API
+```
+Pixel ID: [ID]
+API Access Token: [Token]
+Event Name: {{Event Name}}
+```
+
+## Testing
+
+1. **Preview Mode**: GTM Server Container → Preview
+2. **Validation**:
+   - Client → Server 요청 도달
+   - Server → Platform 전송 확인
+   - Cookie 설정 확인 (1st-party)
+   - Latency < 200ms
+
+## Common Issues
+
+| Issue | Solution |
+|-------|----------|
+| 요청 미도달 | CORS, Custom domain 확인 |
+| Cookie 미설정 | Same-site 정책, 도메인 확인 |
+| Timeout | 리전 최적화, 스케일링 |