CREATE TABLE IF NOT EXISTS collections (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    slug VARCHAR(64) UNIQUE NOT NULL,
    title VARCHAR(128) NOT NULL,
    description TEXT,
    mods JSONB NOT NULL DEFAULT '[]'::jsonb,
    author_id BIGINT,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX IF NOT EXISTS idx_collections_slug ON collections(slug);