Initial commit: React + Django full-stack project setup

- Backend: Django 4.2 + DRF + JWT + GraphQL
- Frontend: React 18 + MobX + styled-components
- Deployment: Docker + Docker Compose + Nginx
- Database: PostgreSQL support
- Documentation: README, INIT, PROJECT_DOCS, TESTING

frontend/src/App.js

@@ -0,0 +1,35 @@
+import React from 'react';
+import { Routes, Route } from 'react-router-dom';
+import styled from 'styled-components';
+
+const Container = styled.div`
+  max-width: 1200px;
+  margin: 0 auto;
+  padding: 20px;
+`;
+
+const Header = styled.header`
+  margin-bottom: 30px;
+  padding-bottom: 20px;
+  border-bottom: 2px solid #eee;
+`;
+
+const Title = styled.h1`
+  margin: 0;
+  font-size: 28px;
+`;
+
+function App() {
+  return (
+    <Container>
+      <Header>
+        <Title>React + Django App</Title>
+      </Header>
+      <Routes>
+        <Route path="/" element={<div>Welcome to the app!</div>} />
+      </Routes>
+    </Container>
+  );
+}
+
+export default App;