feat: PostgreSQL 17 вместо SQLite

pg + connect-pg-simple, async routes, docker-compose, скрипт setup-postgres.

Co-authored-by: Cursor <cursoragent@cursor.com>

postgres/init/01_schema.sql

@@ -0,0 +1,52 @@
+-- PostgreSQL 17 — схема магазина
+
+CREATE TABLE IF NOT EXISTS users (
+  id SERIAL PRIMARY KEY,
+  email TEXT NOT NULL UNIQUE,
+  password_hash TEXT NOT NULL,
+  name TEXT NOT NULL,
+  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+CREATE TABLE IF NOT EXISTS categories (
+  id SERIAL PRIMARY KEY,
+  slug TEXT NOT NULL UNIQUE,
+  name TEXT NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS products (
+  id SERIAL PRIMARY KEY,
+  category_id INTEGER REFERENCES categories(id) ON DELETE SET NULL,
+  slug TEXT NOT NULL UNIQUE,
+  name TEXT NOT NULL,
+  description TEXT NOT NULL DEFAULT '',
+  price_cents INTEGER NOT NULL CHECK (price_cents >= 0),
+  stock INTEGER NOT NULL DEFAULT 0 CHECK (stock >= 0),
+  image_url TEXT,
+  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+CREATE TABLE IF NOT EXISTS orders (
+  id SERIAL PRIMARY KEY,
+  user_id INTEGER NOT NULL REFERENCES users(id),
+  status TEXT NOT NULL DEFAULT 'pending'
+    CHECK (status IN ('pending', 'paid', 'shipped', 'cancelled')),
+  total_cents INTEGER NOT NULL CHECK (total_cents >= 0),
+  customer_name TEXT NOT NULL,
+  customer_email TEXT NOT NULL,
+  customer_phone TEXT NOT NULL DEFAULT '',
+  address TEXT NOT NULL,
+  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+);
+
+CREATE TABLE IF NOT EXISTS order_items (
+  id SERIAL PRIMARY KEY,
+  order_id INTEGER NOT NULL REFERENCES orders(id) ON DELETE CASCADE,
+  product_id INTEGER NOT NULL REFERENCES products(id),
+  quantity INTEGER NOT NULL CHECK (quantity > 0),
+  price_cents INTEGER NOT NULL CHECK (price_cents >= 0)
+);
+
+CREATE INDEX IF NOT EXISTS idx_products_category ON products(category_id);
+CREATE INDEX IF NOT EXISTS idx_orders_user ON orders(user_id);
+CREATE INDEX IF NOT EXISTS idx_products_name ON products(name);