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/POSTGRESQL.md

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+# PostgreSQL — Patterns e Anti-patterns
+
+> Conexão | Schemas | JSONB | Junções | Window Functions | Migrações | EXPLAIN
+
+## Comandos Rápidos
+```bash
+psql "postgresql://user:pass@host:5432/db?sslmode=require"
+psql -h localhost -U user -d db -c "SELECT NOW();"
+psql -h host -U user -d db -f migration.sql
+```
+
+## Schema Design
+```sql
+-- UUIDs para PK distribuído-friendly (ativar extensão primeiro)
+CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
+
+CREATE TABLE users (
+    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
+    email TEXT NOT NULL UNIQUE,
+    name TEXT NOT NULL,
+    role TEXT NOT NULL DEFAULT 'user' CHECK(role IN ('user','admin','moderator')),
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+-- Auto-update updated_at
+CREATE OR REPLACE FUNCTION update_modified_column()
+RETURNS TRIGGER AS $$ BEGIN NEW.updated_at = NOW(); RETURN NEW; END; $$ LANGUAGE plpgsql;
+
+CREATE TRIGGER update_users_modtime BEFORE UPDATE ON users
+FOR EACH ROW EXECUTE FUNCTION update_modified_column();
+
+-- Enum
+CREATE TYPE order_status AS ENUM ('pending','paid','shipped','cancelled');
+```
+
+## JSONB Ops
+```sql
+INSERT INTO orders (metadata) VALUES ('{"source":"web","items":[{"sku":"A1","qty":2}]}'::jsonb);
+
+SELECT * FROM orders WHERE metadata->>'source' = 'web';
+SELECT * FROM orders WHERE metadata->'items' @> '[{"sku":"A1"}]'::jsonb; -- @> contains
+UPDATE orders SET metadata = jsonb_set(metadata, '{source}', '"mobile"') WHERE id = '...';
+SELECT metadata->>'coupon' AS coupon, COUNT(*) FROM orders GROUP BY 1;
+```
+
+## Indexes
+```sql
+CREATE UNIQUE INDEX idx_users_email ON users(email);            -- único
+CREATE INDEX idx_orders_user_created ON orders(user_id, created_at); -- composto
+CREATE INDEX idx_orders_active ON orders(user_id, created_at)  -- parcial
+  WHERE status NOT IN ('delivered','cancelled');
+CREATE INDEX idx_orders_metadata ON orders USING GIN(metadata);  -- GIN para JSONB
+```
+
+## Window Functions
+```sql
+SELECT date, revenue,
+  SUM(revenue) OVER (ORDER BY date)       AS cumulative_revenue,  -- running total
+  AVG(revenue) OVER (PARTITION BY region) AS avg_by_region,
+  RANK() OVER (ORDER BY revenue DESC)      AS ranking
+FROM daily_sales;
+```
+
+## JOINS Rápidos
+```sql
+-- LEFT JOIN pega todos os usuários, mesmo sem pedidos
+SELECT u.name, COUNT(o.id) AS order_count, COALESCE(SUM(o.total), 0) AS total_spent
+FROM users u LEFT JOIN orders o ON o.user_id = u.id
+GROUP BY u.id, u.name HAVING COUNT(o.id) > 5 ORDER BY total_spent DESC;
+```
+
+## CTEs (WITH)
+```sql
+WITH active_users AS (
+  SELECT id, name FROM users WHERE active = true
+)
+SELECT au.name, COUNT(o.id) AS orders
+FROM active_users au LEFT JOIN orders o ON o.user_id = au.id
+GROUP BY au.name;
+```
+
+## EXPLAIN ANALYZE (antes de otimizar)
+```bash
+EXPLAIN ANALYZE SELECT ... -- SEMPRE antes de criar um índice
+```
+
+## Migrations — Padrão
+```bash
+# Criar timestamped
+psql -h host -U user -d db -f migrations/2025-06-19_add_field.sql
+```
+
+## Checklist de Otimização
+- [ ] `EXPLAIN ANALYZE` antes e depois de cada mudança
+- [ ] Medir tempo de resposta alvo antes de otimizar
+- [ ] Evitar `SELECT *` em produção
+- [ ] Criar índices para colunas em `WHERE`, `JOIN`, `ORDER BY`
+- [ ] Índice parcial para subconjuntos pequenos
+- [ ] Partial/Paginado para tabelas grandes