fix(web): Fix web build error with React 19

This commit introduces two changes to fix the web build for Expo 53 and React 19.

First, it creates a separate entry point for the web build (`index.web.js`) that uses the `createRoot` API from `react-dom/client`. This is necessary for React 19.

Second, it adds a `metro.config.js` file to fix a module resolution issue with `react-native`. The configuration forces Metro to resolve `react-native` from the project's `node_modules`, which prevents the `Unable to resolve "../Utilities/Platform"` error.

Author: google-labs-jules[bot]

frontend/metro.config.js

@@ -0,0 +1,21 @@
+const { getDefaultConfig } = require('expo/metro-config');
+const path = require('path');
+
+const projectRoot = __dirname;
+const workspaceRoot = path.resolve(projectRoot, '../..');
+
+const config = getDefaultConfig(projectRoot);
+
+// 1. Watch all files in the monorepo
+config.watchFolders = [workspaceRoot];
+// 2. Let Metro know where to resolve packages and in what order
+config.resolver.nodeModulesPaths = [
+  path.resolve(projectRoot, 'node_modules'),
+  path.resolve(workspaceRoot, 'node_modules'),
+];
+// 3. Force Metro to resolve certain dependencies from the project root
+config.resolver.extraNodeModules = {
+  'react-native': path.resolve(projectRoot, 'node_modules/react-native'),
+};
+
+module.exports = config;