fix: control CodeSee via .env variable (#42428)

client/.babelrc.js

@@ -0,0 +1,75 @@
+require('dotenv').config({ path: '../.env' });
+const config = {
+  presets: [
+    [
+      '@babel/preset-env',
+      {
+        loose: true,
+        modules: false,
+        useBuiltIns: 'usage',
+        corejs: 2,
+        shippedProposals: true,
+        targets: {
+          browsers: ['>0.25%', 'not dead']
+        }
+      }
+    ],
+    [
+      '@babel/preset-react',
+      {
+        useBuiltIns: true,
+        pragma: 'React.createElement'
+      }
+    ],
+    '@babel/preset-typescript'
+  ],
+  plugins: [
+    'preval',
+    '@babel/plugin-syntax-dynamic-import',
+    'babel-plugin-macros',
+    [
+      '@babel/plugin-transform-runtime',
+      {
+        helpers: true,
+        regenerator: true
+      }
+    ],
+    [
+      'babel-plugin-transform-imports',
+      {
+        'react-bootstrap': {
+          transform: 'react-bootstrap/lib/${member}',
+          preventFullImport: true
+        }
+      }
+    ],
+    [
+      'prismjs',
+      {
+        languages: [
+          'clike',
+          'css',
+          'html',
+          'javascript',
+          'markup',
+          'mathml',
+          'python',
+          'svg',
+          'xml',
+          'sql',
+          'typescript'
+        ],
+        theme: 'default',
+        css: true,
+        plugins: ['line-numbers']
+      }
+    ]
+  ]
+};
+if (
+  process.env.FREECODECAMP_NODE_ENV === 'development' &&
+  process.env.CODESEE === 'true'
+) {
+  config.plugins.push(['@codesee/instrument', { hosted: true }]);
+}
+module.exports = config;