ux(mobile): remove barra de navegacao inferior fixa (menu fica no hamburger)

- remove MobileBottomNav do layout + pb-24 que reservava o espaco
- navegacao mobile passa a ser so pelo menu sanduiche

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

frontend/App.tsx

@@ -509,22 +509,12 @@ const App: React.FC = () => {
             </>
           )}
 
-          <div className="flex-1 overflow-y-auto p-4 md:p-8 pb-24 md:pb-8 scroll-smooth">
+          <div className="flex-1 overflow-y-auto p-4 md:p-8 scroll-smooth">
             <div className="max-w-7xl mx-auto h-full">
               {renderView()}
             </div>
           </div>
         </main>
-
-        {!isStandaloneView && (
-          <MobileBottomNav
-            activeTab={currentView}
-            role={currentRole}
-            clinColor={clinColor}
-            onNavigate={handleNavigate}
-            onMore={() => setSidebarOpen(true)}
-          />
-        )}
       </div>
       <ToastContainer />
     </>