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/17-seo-schema-generator/desktop/templates/website.json

@@ -0,0 +1,25 @@
+{
+  "@context": "https://schema.org",
+  "@type": "WebSite",
+  "name": "{{site_name}}",
+  "alternateName": "{{alternate_name}}",
+  "url": "{{url}}",
+  "description": "{{description}}",
+  "inLanguage": "{{language}}",
+  "potentialAction": {
+    "@type": "SearchAction",
+    "target": {
+      "@type": "EntryPoint",
+      "urlTemplate": "{{search_url_template}}"
+    },
+    "query-input": "required name=search_term_string"
+  },
+  "publisher": {
+    "@type": "Organization",
+    "name": "{{publisher_name}}",
+    "logo": {
+      "@type": "ImageObject",
+      "url": "{{logo_url}}"
+    }
+  }
+}