feat: Implement alert system and network connectivity handling, refactor error handling across screens

components/OfflineScreen.tsx

@@ -0,0 +1,48 @@
+import React from 'react';
+import { View, Text, TouchableOpacity } from 'react-native';
+import { SafeAreaView } from 'react-native-safe-area-context';
+import { WifiOff, RefreshCw } from 'lucide-react-native';
+
+interface OfflineScreenProps {
+  onRetry: () => void;
+  isRetrying?: boolean;
+}
+
+export default function OfflineScreen({ onRetry, isRetrying = false }: OfflineScreenProps) {
+  return (
+    <SafeAreaView className="flex-1 bg-white">
+      <View className="flex-1 items-center justify-center px-8">
+        {/* Icona con cerchio di sfondo */}
+        <View className="bg-gray-100 p-6 rounded-full mb-6">
+          <WifiOff size={64} className="text-gray-400" />
+        </View>
+
+        <Text className="text-2xl font-bold text-gray-800 mb-2 text-center">
+          Sei Offline
+        </Text>
+        
+        <Text className="text-base text-gray-500 text-center mb-10 leading-6">
+          Sembra che non ci sia connessione a internet.{'\n'}Controlla il Wi-Fi o i dati mobili e riprova.
+        </Text>
+
+        {/* Pulsante Riprova */}
+        <TouchableOpacity
+          onPress={onRetry}
+          disabled={isRetrying}
+          className={`flex-row items-center justify-center w-full py-4 rounded-xl gap-4 ${
+            isRetrying ? 'bg-gray-300' : 'bg-[#099499] active:bg-[#077f83]'
+          }`}
+        >
+          <RefreshCw 
+            size={20} 
+            color="white" 
+            className={`${isRetrying ? 'animate-spin' : ''}`} // TODO: animate-spin richiede config tailwind o gestiscilo manualmente
+          />
+          <Text className="text-white font-bold text-lg">
+            {isRetrying ? 'Controllo...' : 'Riprova'}
+          </Text>
+        </TouchableOpacity>
+      </View>
+    </SafeAreaView>
+  );
+}