Add single container Docker setup (backend + frontend in one container)

backend/src/app.js

@@ -100,6 +100,23 @@ app.use(express.urlencoded({ extended: true }));
 // Serve static files (landing page)
 app.use(express.static('src/public'));
 
+// Serve frontend build files (if exists, for production)
+const path = require('path');
+const frontendDistPath = path.join(__dirname, '../../frontend/dist');
+const fs = require('fs');
+if (fs.existsSync(frontendDistPath)) {
+  app.use(express.static(frontendDistPath));
+  
+  // SPA fallback: serve index.html for all non-API routes
+  app.get('*', (req, res, next) => {
+    // Skip API routes and tracking routes
+    if (req.path.startsWith('/api') || req.path.startsWith('/t/') || req.path.startsWith('/health')) {
+      return next();
+    }
+    res.sendFile(path.join(frontendDistPath, 'index.html'));
+  });
+}
+
 // Session middleware
 app.use(session(sessionConfig));