AcaiAPI data layer + CocoDB facade

AcaiAPI: PDO-based data access layer (prepared statements, JOIN relation
loading, batch upload fetching) developed on villagrancanaria.
CocoDB_alias declares the CocoDB facade delegating to AcaiAPI; the
legacy implementation stays available as CocoDB_old.

cms/lib/classes/CocoDB.php

@@ -1,5 +1,6 @@
 <?php
-class CocoDB
+require_once __DIR__ . '/CocoDB_alias.php';
+class CocoDB_old
 {
     public static $tableCache = [];
     public static $uploadColumns = [];