Initial commit: Set up Garmin Health Lab project structure

- Initialize monorepo with root workspace configuration
- Set up Express.js backend with TypeScript
- Set up React 18 frontend with TypeScript
- Create database schema with SQLite
- Implement project architecture and documentation
- Add development and deployment guidelines

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

client/src/App.tsx

@@ -0,0 +1,26 @@
+import React from 'react';
+import { BrowserRouter as Router, Routes, Route } from 'react-router-dom';
+import Layout from './components/Layout';
+import Dashboard from './pages/Dashboard';
+import DataSync from './pages/DataSync';
+import Analysis from './pages/Analysis';
+import Recommendations from './pages/Recommendations';
+import Settings from './pages/Settings';
+
+function App() {
+  return (
+    <Router>
+      <Layout>
+        <Routes>
+          <Route path="/" element={<Dashboard />} />
+          <Route path="/sync" element={<DataSync />} />
+          <Route path="/analysis" element={<Analysis />} />
+          <Route path="/recommendations" element={<Recommendations />} />
+          <Route path="/settings" element={<Settings />} />
+        </Routes>
+      </Layout>
+    </Router>
+  );
+}
+
+export default App;