/**
 * Unwrap the unified response envelope:
 *   {"ok": true, "data": ...} -> returns { success: true, ...data }
 *   {"ok": false, "error": ...} -> returns { success: false, error: message }
 * Also supports legacy format for backward compat.
 */
export function unwrap(json) {
    if (typeof json.ok === 'boolean') {
        if (json.ok) {
            const d = json.data || {};
            return { success: true, ...(Array.isArray(d) ? { items: d } : d) };
        }
        return { success: false, error: json.error?.message || 'Unknown error' };
    }
    return json;
}