feat: add React app shell with routing

src/App.tsx

@@ -0,0 +1,14 @@
+import { Routes, Route } from "react-router-dom";
+import LoginPage from "./pages/LoginPage";
+import WorkspacePage from "./pages/WorkspacePage";
+import ChatPage from "./pages/ChatPage";
+
+export default function App() {
+  return (
+    <Routes>
+      <Route path="/" element={<LoginPage />} />
+      <Route path="/workspaces" element={<WorkspacePage />} />
+      <Route path="/workspaces/:workspaceId" element={<ChatPage />} />
+    </Routes>
+  );
+}

src/main.tsx

@@ -1,8 +1,12 @@
 import React from "react";
 import ReactDOM from "react-dom/client";
+import { BrowserRouter } from "react-router-dom";
+import App from "./App";
 
 ReactDOM.createRoot(document.getElementById("root")!).render(
   <React.StrictMode>
-    <div>Loading…</div>
+    <BrowserRouter>
+      <App />
+    </BrowserRouter>
   </React.StrictMode>
 );

src/pages/ChatPage.tsx

@@ -0,0 +1,3 @@
+export default function ChatPage() {
+  return <div>Chat</div>;
+}

src/pages/LoginPage.tsx

@@ -0,0 +1,3 @@
+export default function LoginPage() {
+  return <div>Login</div>;
+}

src/pages/WorkspacePage.tsx

@@ -0,0 +1,3 @@
+export default function WorkspacePage() {
+  return <div>Workspaces</div>;
+}