API Tidy

- Remove old client ID queries, these are now built into the API keys. If a key has access to all clients, a client ID can be provided in the query.
- Small fixes to assets URI lookup
- Add read endpoint for vendors

api/v1/products/read.php

@@ -9,13 +9,11 @@ require_once '../require_get_method.php';
 
 if (isset($_GET['product_id']) && $client_id == "%") {
     // product via ID (single)
-
     $id = intval($_GET['product_id']);
     $sql = mysqli_query($mysqli, "SELECT * FROM products WHERE product_id = '$id'");
 
 } elseif ($client_id == "%") {
     // All products
-
     $sql = mysqli_query($mysqli, "SELECT * FROM products ORDER BY product_id LIMIT $limit OFFSET $offset");
 }