add Zustand and del unnecessary files

app/(tabs)/add.jsx

@@ -6,7 +6,7 @@ import {
   ScrollView,
 } from "react-native";
 import { TextInput, Button, Snackbar } from "react-native-paper";
-import { addLocation } from "@/api/locations";
+import useLocationStore from "@/locationStore";
 
 export default function FormScreen() {
   const [formData, setFormData] = useState({
@@ -19,7 +19,9 @@ export default function FormScreen() {
   const [message, setMessage] = useState("");
   const [visible, setVisible] = useState(false);
 
-  const handleAddLocation = () => {
+  const addLocation = useLocationStore((state) => state.addLocation);
+
+  const handleAddLocation = async () => {
     if (
       formData.name &&
       formData.description &&
@@ -36,8 +38,7 @@ export default function FormScreen() {
         population: parseInt(formData.population),
       };
 
-      addLocation(newLocation);
-
+      const added = await addLocation(newLocation);
       setFormData({
         name: "",
         description: "",
@@ -45,7 +46,7 @@ export default function FormScreen() {
         area: 0,
         population: 0,
       });
-      if(addLocation != null) {
+      if (added != null) {
         setMessage("Lokalizacja została dodana!");
         setVisible(true);
       } else {