Fixing provider state and wallet change listener, formatting balance

Co-authored-by: RcleydsonR <rafael.cleydson@gmail.com>

src/store/ether.ts

@@ -1,21 +1,16 @@
-import type { ethers } from "ethers";
 import { defineStore } from "pinia";
 
 export const useEtherStore = defineStore("ether", {
   state: () => ({
     walletAddress: "",
-    balance: 0,
-    provider: null as ethers.providers.Web3Provider | null,
+    balance: "",
   }),
   actions: {
     setWalletAddress(walletAddress: string) {
       this.walletAddress = walletAddress;
     },
-    setBalance(balance: number) {
+    setBalance(balance: string) {
       this.balance = balance;
     },
-    setProvider(provider: ethers.providers.Web3Provider | null) {
-      this.provider = provider;
-    },
   },
 });