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>

infraestrutura/skills/authentik/SKILL.md

@@ -1,11 +1,7 @@
 ---
 name: authentik
-description: Authentik SSO management via API v3. Users, groups, applications, providers, flows, events. Use when user mentions "authentik", "sso", "auth.descomplicar", "identity provider", "oauth2 provider", "autenticacao centralizada", "single sign-on".
-author: Descomplicar® Crescimento Digital
-version: 1.0.0
-quality_score: 75
-user_invocable: true
-desk_task: 1484
+description: Gestão do Authentik SSO via API v3 — utilizadores, grupos, aplicações, providers, flows e eventos em auth.descomplicar.pt.
+disable-model-invocation: true
 ---
 
 # /authentik - Gestao Authentik via API v3