add prettier github action

.github/workflows/prettier.yml

@@ -0,0 +1,28 @@
+name: Prettier
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  prettier:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: "20"
+
+      - name: Install dependencies
+        run: npm install
+
+      - name: Run Prettier
+        run: npx prettier --check .

src/App.jsx

@@ -1,4 +1,4 @@
-import React, { useState, useEffect } from "react";
+import { useState, useEffect } from "react";
 
 import "./App.css";
 import StructureVisualizer from "./StructureVisualizer";