feat: biblioteca inteligente libs/ + 5 novas skills (20 skills total)

NOVAS SKILLS:
- next-best-practices      v0.1.0  (CLEAN) — Next.js App Router, RSC, caching, data
- nextjs-patterns          v1.0.0  (CLEAN) — Next.js 15: Server Actions, route handlers
- vite                     v1.0.0  (CLEAN) — env vars, aliases, proxy, CJS compat
- uncle-bob                v1.0.0  (CLEAN) — Clean Code, SOLID, Clean Architecture
- clean-code-review        v1.0.0  (CLEAN) — naming, guard clauses, anti-patterns, refactoring
- vue                      v1.0.0  (CLEAN) — Vue framework
- vue-composition-api-best-practices v1.0.0 (CLEAN) — composables, Pinia, reactivity

BIBLIOTECA INTELIGENTE libs/ (10 dominios, 11 arquivos):
- typescript/ — TS safe + generics gotchas
- react/ — Next.js App Router + Vite config
- vue/ — Composition API + Pinia
- linux/ — System diagnostic cheatsheet
- database/ — PostgreSQL + MySQL patterns
- browser/ — Chromium CLI + E2E testing
- security/ — SAST audit (OWASP Top 10)
- best-practices/ — Clean Code + SOLID + Clean Architecture
- deploy/ — Docker multi-stack + OpenClaw ops
- + INDEX.md como guia de navegacao

.learnings/ — LRN-20260519-003 criado (biblioteca compartilhada)

libs/database/MYSQL.md

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+# MySQL — Patterns e Anti-patterns
+
+> Conexão | Schemas | JSON | InnoDB | Otimização
+
+## Comandos Rápidos
+```bash
+mysql -h localhost -u root -p mydb
+mysql -h host -u user -p -e "SELECT NOW();" mydb
+mysql -h host -u user -p mydb < migration.sql
+```
+
+## Schema Design
+```sql
+CREATE TABLE users (
+    id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
+    email VARCHAR(255) NOT NULL UNIQUE,
+    name VARCHAR(255) NOT NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
+```
+> **SEMPRE** `ENGINE=InnoDB` — transações, FK, row-level locking. `utf8mb4` — suporta emoji e acentos completos.
+
+## JSON Ops
+```sql
+CREATE TABLE orders (
+    id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
+    metadata JSON,
+    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+);
+
+SELECT * FROM orders WHERE JSON_EXTRACT(metadata, '$.source') = 'web';
+-- Shorthand (MySQL 8+):
+SELECT * FROM orders WHERE metadata->>'$.source' = 'web';
+```
+
+## Indexes
+```sql
+-- Index composto
+CREATE INDEX idx_orders_user_id ON orders(user_id);
+
+-- Índice parcial (simulado com generated column + índice)
+ALTER TABLE orders ADD COLUMN is_active TINYINT(1) 
+  GENERATED ALWAYS AS (status != 'cancelled') STORED;
+CREATE INDEX idx_orders_active ON orders(is_active);
+```
+
+## Joins e Agregações
+```sql
+SELECT u.name, o.total, o.status
+FROM users u
+INNER JOIN orders o ON o.user_id = u.id
+WHERE o.created_at > '2026-01-01'
+ORDER BY o.total DESC
+LIMIT 10;
+
+SELECT status, COUNT(*) AS cnt, SUM(total) AS revenue
+FROM orders GROUP BY status HAVING cnt > 5;
+```
+
+## Diferenças principais vs PostgreSQL
+| Aspecto | MySQL | PostgreSQL |
+|---------|-------|-------------|
+| Auto-increment | `AUTO_INCREMENT` | `SERIAL` / `IDENTITY` |
+| UUID padrão | Requer plugin (não padrão) | `uuid-ossp` built-in |
+| JSON | `JSON` type (baixa performance em queries) | `JSONB` indexável |
+| CTEs | Suportado (MySQL 8+) | Nativo desde sempre |
+| Window Functions | MySQL 8+ | Nativo |
+| Transactions | InnoDB obrigatório | Sempre |
+| Null-safe join | `<=>` (spaceship operator) | `IS NOT DISTINCT FROM` |