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- Delete class.Log (unused), class.Mobile_Detect (outdated UA detection)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>

tests/Unit/Domain/Cache/CacheRepositoryTest.php

@@ -8,7 +8,7 @@ use Domain\Cache\CacheRepository;
  * Testy dla CacheRepository
  *
  * Testujemy logikę Redis (mockowaną) oraz strukturę odpowiedzi.
- * Czyszczenie katalogów delegowane do \S::delete_dir() - nietestowalne unit testami.
+ * Czyszczenie katalogów delegowane do \Shared\Helpers\Helpers::delete_dir() - nietestowalne unit testami.
  */
 class CacheRepositoryTest extends TestCase
 {