Remove HTML Preview Tool from navigation and add to gitignore

- Removed HTML Preview Tool from navigation menu in Layout.js
- Cleaned up unused Code import
- Added HTML Preview related files to .gitignore
- Project builds successfully without HTML Preview Tool

package.json

@@ -4,24 +4,33 @@
   "description": "Web Developer Tools MVP - Utilities Toolkit",
   "private": true,
   "dependencies": {
+    "@codemirror/commands": "^6.8.1",
+    "@codemirror/lang-css": "^6.3.1",
+    "@codemirror/lang-html": "^6.4.9",
+    "@codemirror/lang-javascript": "^6.2.4",
+    "@codemirror/search": "^6.5.11",
+    "@codemirror/theme-one-dark": "^6.1.3",
     "@testing-library/jest-dom": "^5.16.4",
     "@testing-library/react": "^13.3.0",
     "@testing-library/user-event": "^13.5.0",
+    "@uiw/react-codemirror": "^4.24.2",
+    "codemirror": "^5.65.19",
+    "diff-match-patch": "^1.0.5",
+    "js-beautify": "^1.15.4",
+    "lucide-react": "^0.263.1",
+    "papaparse": "^5.4.1",
     "react": "^18.2.0",
+    "react-codemirror2": "^8.0.1",
     "react-dom": "^18.2.0",
     "react-router-dom": "^6.3.0",
     "react-scripts": "5.0.1",
-    "js-beautify": "^1.14.9",
-    "diff-match-patch": "^1.0.5",
-    "papaparse": "^5.4.1",
     "serialize-javascript": "^6.0.0",
-    "lucide-react": "^0.263.1",
     "web-vitals": "^2.1.4"
   },
   "devDependencies": {
-    "tailwindcss": "^3.3.0",
     "autoprefixer": "^10.4.14",
-    "postcss": "^8.4.24"
+    "postcss": "^8.4.24",
+    "tailwindcss": "^3.3.0"
   },
   "scripts": {
     "start": "react-scripts start",