ver. 0.283: Legacy class cleanup — S, Html, Email, Image, Log, Mobile_Detect → Shared namespace

- Migrate class.S → Shared\Helpers\Helpers (140+ files), remove 12 unused methods
- Migrate class.Html → Shared\Html\Html
- Migrate class.Email → Shared\Email\Email
- Migrate class.Image → Shared\Image\ImageManipulator
- Delete class.Log (unused), class.Mobile_Detect (outdated UA detection)
- Remove grid library loading from admin (index.php, ajax.php)
- Replace gridEdit usage in 10 admin templates with grid-edit-replacement.php
- Fix grid-edit-replacement.php AJAX to send values as JSON (grid.js compat)
- Remove mobile layout conditionals (m_html/m_css/m_js) from Site + LayoutsRepository
- Remove \Log::save_log() calls from OrderAdminService, ShopOrder, Order

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

autoload/front/controls/class.ShopCoupon.php

@@ -4,7 +4,7 @@ class ShopCoupon
 {
   public static function delete_coupon()
   {
-    \S::delete_session( 'coupon' );
+    \Shared\Helpers\Helpers::delete_session( 'coupon' );
     header( 'Location: /koszyk' );
     exit;
   }
@@ -12,12 +12,12 @@ class ShopCoupon
   public static function use_coupon()
   {
     $coupon = new \shop\Coupon( 0 );
-    $coupon -> load_from_db_by_name( (string)\S::get( 'coupon' ) );
+    $coupon -> load_from_db_by_name( (string)\Shared\Helpers\Helpers::get( 'coupon' ) );
 
     if ( $coupon -> is_available() )
-      \S::set_session( 'coupon', $coupon );
+      \Shared\Helpers\Helpers::set_session( 'coupon', $coupon );
     else
-      \S::alert( 'Podany kod rabatowy jest nieprawidłowy.' );
+      \Shared\Helpers\Helpers::alert( 'Podany kod rabatowy jest nieprawidłowy.' );
 
     header( 'Location: /koszyk' );
     exit;