chore: initial monorepo scaffold + WDS Phase 1+2 artifacts

- Nx 22.7 monorepo (pnpm 11.1, TypeScript 5.9, Node 24)
- apps/api: NestJS 11 (CJS conforme CODING-RULES.md PGD-DB-004)
- apps/web: React 19 + Vite 8 (ESM)
- libs/shared/api-interface: Zod contract base
- Docker Compose dev: Postgres 18, Valkey 8, MinIO, Mailpit
- WDS artifacts:
  - design-artifacts/A-Product-Brief/ (5 docs canônicos + 16 dialogs)
  - design-artifacts/B-Trigger-Map/ (hub + 4 personas + feature impact)
- Stack canon: STACK.md v2.2 + CODING-RULES.md v2.0 + brand.md
- AGENTS.md + README.md como entrada para devs/agentes

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.agents/skills/bmad-agent-tech-writer/explain-concept.md

@@ -0,0 +1,20 @@
+---
+name: explain-concept
+description: Create clear technical explanations with examples
+menu-code: EC
+---
+
+# Explain Concept
+
+Create a clear technical explanation with examples and diagrams for a complex concept.
+
+## Process
+
+1. **Understand the concept** — Clarify what needs to be explained and the target audience
+2. **Structure** — Break it down into digestible sections using a task-oriented approach
+3. **Illustrate** — Include code examples and Mermaid diagrams where helpful
+4. **Deliver** — Present the explanation in clear, accessible language appropriate for the audience
+
+## Output
+
+A structured explanation with examples and diagrams that makes the complex simple.