CREATE TABLE IF NOT EXISTS user_profiles (
  user_id TEXT PRIMARY KEY,
  display_name TEXT,
  avatar_url TEXT,
  timezone TEXT,
  locale TEXT,
  profile_data JSONB DEFAULT '{}',
  preferences JSONB DEFAULT '{}',
  personalization JSONB DEFAULT '{}',
  created_at TIMESTAMP DEFAULT NOW() NOT NULL,
  updated_at TIMESTAMP DEFAULT NOW() NOT NULL
);