feat: add loading state and full-page loader component; update payment page and application layout to improve user experience

lib/atoms.ts

@@ -15,6 +15,7 @@ export const formulaResultAtom = atom("");
 export const deviceCartAtom = atom<Device[]>([]);
 export const cartDrawerOpenAtom = atom(false);
 export const WalletDrawerOpenAtom = atom(false);
+export const loadingDevicesToPayAtom = atom(false);
 
 // Export the atoms with their store
 export const atoms = {
@@ -27,4 +28,5 @@ export const atoms = {
 	deviceCartAtom,
 	cartDrawerOpenAtom,
 	walletTopUpValue,
+	loadingDevicesToPayAtom,
 };