feat: refactor 30+ skills to Anthropic progressive disclosure pattern

- All SKILL.md files now <500 lines (avg reduction 69%)
- Detailed content extracted to references/ subdirectories
- Frontmatter standardised: only name + description (Anthropic standard)
- New skills: brand-guidelines, spec-coauthor, report-templates, skill-creator
- Design skills: anti-slop guidelines, premium-proposals reference
- Removed non-standard frontmatter fields (triggers, version, author, category)

Plugins affected: infraestrutura, marketing, dev-tools, crm-ops, gestao,
core-tools, negocio, perfex-dev, wordpress, design-media

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

metabase/knowledge/datasets.json

@@ -11,11 +11,6 @@
       "description": "NotebookLM - conhecimento curado (se notebooks BI forem criados)",
       "query_tool": "mcp__notebooklm__notebook_query",
       "notebooks": []
-    },
-    "dify_kb": {
-      "description": "Dify KB - datasets relacionados (fallback)",
-      "query_tool": "mcp__dify-kb__dify_kb_retrieve_segments",
-      "datasets": []
     }
   }
 }