사용자 인증 테이블

AUTH TABLESCREATE TABLE users (  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),  email VARCHAR(255) UNIQUE NOT NULL,  password_hash TEXT NOT NULL,  email_verified BOOLEAN DEFAULT false,  created_at TIMESTAMPTZ DEFAULT NOW());CREATE TABLE refresh_tokens (  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),  user_id UUID REFERENCES users(id) ON DELETE CASCADE,  token TEXT UNIQUE NOT NULL,  expires_at TIMESTAMPTZ NOT NULL);