fix(config): remove duplicates and fix file extensions

Author: ThierryRakotomanana

src/content/guides/typescript.mdx

@@ -59,8 +59,7 @@ Let's set up a configuration to support JSX and compile TypeScript down to ES5..
     "moduleResolution": "bundler",
     "target": "esnext",
     "jsx": "react-jsx",
-    "allowJs": true,
-    "moduleResolution": "node"
+    "allowJs": true
   },
   "include": ["src/**/*"],
   "exclude": ["node_modules"]
@@ -187,7 +186,7 @@ If you use [`compilerOptions.paths`](https://www.typescriptlang.org/tsconfig#pat
 
 `resolve.tsconfig` accepts `boolean | string | object`:
 
-**webpack.config.js**
+**webpack.config.ts**
 
 ```js
 export default {
@@ -266,7 +265,6 @@ To enable source maps, we must configure TypeScript to output inline source maps
       "target": "esnext",
       "jsx": "react-jsx",
       "allowJs": true,
-      "moduleResolution": "node"
   },
     "include": ["src/**/*"],
     "exclude": ["node_modules"]
@@ -275,7 +273,7 @@ To enable source maps, we must configure TypeScript to output inline source maps
 
 Now we need to tell webpack to extract these source maps and include in our final bundle:
 
-**webpack.config.js**
+**webpack.config.ts**
 
 ```diff
  import path from "node:path";