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>

index.html

@@ -9,10 +9,10 @@
   <meta http-equiv="Pragma" content="no-cache" />
   <meta http-equiv="Expires" content="0" />
 
-  <title>BOHA Interni system</title>
+  <title>Interní systém</title>
 
   <meta name="robots" content="noindex, nofollow" />
-  <meta name="apple-mobile-web-app-title" content="BOHA System" />
+  <meta name="apple-mobile-web-app-title" content="Interní systém" />
 
   <link rel="icon" type="image/png" href="/favicon-96x96.png" sizes="96x96" />
   <link rel="icon" type="image/svg+xml" href="/favicon.svg" />