feat: use bignumber.

frontend/src/pages/client/pages/components/InteractionsWidget.tsx

@@ -17,7 +17,7 @@ import {
   ERC20Mock__factory,
   OrdersExchange__factory,
 } from "../../../../typechain";
-import { ethers } from "ethers";
+import { BigNumber, ethers } from "ethers";
 import { ASSETS } from "../../../../constants/Assets";
 import { useForm } from "react-hook-form";
 import { zodResolver } from "@hookform/resolvers/zod";
@@ -71,7 +71,7 @@ export const InteractionsWidget: React.FC = () => {
         if (!value) {
           await stableContract.approve(
             process.env.REACT_APP_SWAP_CONTRACT_ADDRESS as string,
-            data.amount * 10 ** 6
+            BigNumber.from(data.amount).mul(10 ** 6)
           );
         } else {
           const contract = new ERC20Mock__factory()
@@ -80,13 +80,13 @@ export const InteractionsWidget: React.FC = () => {
 
           await contract.approve(
             process.env.REACT_APP_SWAP_CONTRACT_ADDRESS as string,
-            data.amount * 10 ** 18
+            BigNumber.from(data.amount).mul(10 ** 18)
           );
         }
 
         const tx = await contract.scheduleOrder(
           ASSETS[asset].address!,
-          data.amount * 10 ** (!value ? 6 : 18),
+          BigNumber.from(data.amount).mul(10 ** (!value ? 6 : 18)),
           !value
         );