[FIX] website_sale: /shop 500 error if category is not model converter

The /shop route can take a `category` argument (a model converter).
  `/shop/category/<model("product.public.category"[..]):category>`

But if that `category` argument is passed through URL query string
(?category=9), it will raise an error when doing
  `category.can_access_from_current_website()`
as it is an integer since it did not went through the model converter

Note: Among probably others, that type of route is used when changing product
      order on shop

Closes #27490, closes #27724

addons/website_sale/controllers/main.py

@@ -189,8 +189,11 @@ class WebsiteSale(ProductConfiguratorController):
         '''/shop/category/<model("product.public.category", "[('website_id', 'in', (False, current_website_id))]"):category>/page/<int:page>'''
     ], type='http', auth="public", website=True)
     def shop(self, page=0, category=None, search='', ppg=False, **post):
-        if category and not category.can_access_from_current_website():
-            raise NotFound()
+        if category:
+            category = request.env['product.public.category'].search([('id', '=', int(category))], limit=1)
+            if not category or not category.can_access_from_current_website():
+                raise NotFound()
+
         if ppg:
             try:
                 ppg = int(ppg)
@@ -200,11 +203,6 @@ class WebsiteSale(ProductConfiguratorController):
         else:
             ppg = PPG
 
-        if category:
-            category = request.env['product.public.category'].search([('id', '=', int(category))], limit=1)
-            if not category:
-                raise NotFound()
-
         attrib_list = request.httprequest.args.getlist('attrib')
         attrib_values = [[int(x) for x in v.split("-")] for v in attrib_list if v]
         attributes_ids = {v[0] for v in attrib_values}