feat: mobilni responsivita, testy, klavesove zkratky, drag & drop, univerzalizace

- Mobile responsive CSS (touch targets 44px, iOS anti-zoom, reduced motion)
- Vitest setup s 39 testy (formatters, attendanceHelpers, useTableSort)
- Klavesove zkratky (Shift+? napoveda, Ctrl+S ulozit, navigace)
- Drag & drop pro polozky nabidek (@dnd-kit, SortableRow, useSortableList)
- Univerzalizace: odstraneni BOHA brandingu z UI, emailu, PDF
- Smazany nepotrebne soubory (deploy.sh, AUTH_SYSTEM.md, example_design, .htaccess)
- CORS konfigurovatelny pres env promennou

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

src/admin/pages/OfferDetail.jsx

@@ -330,16 +330,6 @@ export default function OfferDetail() {
     setItems(prev => prev.length > 1 ? prev.filter((_, i) => i !== index) : prev)
   }
 
-  const moveItem = (index, direction) => {
-    setItems(prev => {
-      const newItems = [...prev]
-      const target = index + direction
-      if (target < 0 || target >= newItems.length) return prev
-      ;[newItems[index], newItems[target]] = [newItems[target], newItems[index]]
-      return newItems
-    })
-  }
-
   const addItemFromTemplate = (template) => {
     setItems(prev => [...prev, {
       _key: `item-${++_keyCounter}`,
@@ -921,10 +911,10 @@ export default function OfferDetail() {
 
       <OfferItemsSection
         items={items}
+        setItems={setItems}
         updateItem={updateItem}
         addItem={addItem}
         removeItem={removeItem}
-        moveItem={moveItem}
         itemTemplates={itemTemplates}
         showItemTemplateMenu={showItemTemplateMenu}
         setShowItemTemplateMenu={setShowItemTemplateMenu}