feat(ui): versão vX.Y.Z fixa no canto inferior direito (todas as telas, lê /api/version)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/App.tsx

@@ -8,6 +8,7 @@ import {
 } from 'lucide-react';
 
 import { ToastContainer } from './components/Toast.tsx';
+import { useAppVersion } from './buildInfo.ts';
 
 import { Dashboard } from './views/Dashboard.tsx';
 import { LeadsView } from './views/LeadsView.tsx';
@@ -265,6 +266,7 @@ const MobileBottomNav: React.FC<{
 
 // ------- App -------
 const App: React.FC = () => {
+  const ver = useAppVersion();
   const [isSidebarOpen, setSidebarOpen] = useState(false);
   const [, forcePwRerender] = useState(0); // re-avalia o modal de troca obrigatória de senha
   const currentRole = HybridBackend.getCurrentRole();
@@ -577,6 +579,10 @@ const App: React.FC = () => {
         </main>
       </div>
       <ToastContainer />
+      {/* Versão sempre visível no canto inferior direito (lê /api/version; não bloqueia cliques) */}
+      <div className="fixed bottom-1.5 right-2 z-40 pointer-events-none select-none text-[10px] font-mono text-gray-400/70">
+        {ver.version}
+      </div>
     </>
   );
 };