Ajout connexion au serveur

client/app/_layout.tsx

@@ -17,6 +17,7 @@ export default function RootLayout() {
         <ThemeProvider value={colorScheme === 'dark' ? DarkTheme : DefaultTheme}>
           <Stack>
             <Stack.Screen name="(tabs)" options={{ headerShown: false }} />
+            <Stack.Screen name="login" options={{ title: "Connexion" }} />
             <Stack.Screen name="+not-found" />
           </Stack>
           <StatusBar style="auto" />