Args:
    query: words to match in product names, case-insensitive
        (e.g. "heinz baked beans", "kerrygold butter", "pringles").
    store: optionally filter to one of "aldi", "tesco", "supervalu",
        "dunnes". Leave it out to search all four.
    limit: how many results to return in total (default 10).

Returns the matching product rows: store, SKU id, name, brand, price,
unit_price (€/kg or €/L), pack_size, category_path, url. Matches on the
name only: no ingredient, nutrition or offer filters, and no price sorting.