Update Preorder Messages & Dates

Manage the global out-of-stock preorder message and per-manufacturer restock lead times for the OpenCart 3 catalog. The CKEditor block stores HTML in pd_preorder_notes (id 1). Each manufacturer row accepts a days to restock value saved to pd_preorder_dates, from which a projected restock_date is calculated.

• Update Note — saves the CKEditor preorder message only; it does not push changes to individual products.
• Update Products with Preorder Dates & Preorder Note — upserts all manufacturer restock rows, then propagates calculated restock dates, a 100% preorder deposit, cleared restock values, and the shared preorder note across oc_product and oc_product_description (language_id 1).
• Products with a custom restock_message retain their existing date_restock; all other out-of-stock fields are still updated.