feat: Implement local chat saving and history management using Zustand and AsyncStorage.

package.json

@@ -14,6 +14,7 @@
     "@babel/plugin-transform-runtime": "^7.29.0",
     "@babel/runtime": "^7.28.6",
     "@expo/vector-icons": "^15.0.3",
+    "@react-native-async-storage/async-storage": "2.2.0",
     "@react-navigation/bottom-tabs": "^7.4.0",
     "@react-navigation/elements": "^2.6.3",
     "@react-navigation/native": "^7.1.8",