feat: add Passenger app.js for Plesk deployment

Node.js entry point that serves static frontend files and proxies
/api/ requests to the FastAPI backend on port 8000.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

deploy/app.js

@@ -0,0 +1,80 @@
+const http = require('http');
+const fs = require('fs');
+const path = require('path');
+
+const DIST_DIR = path.join(__dirname, 'dist');
+
+const MIME_TYPES = {
+  '.html': 'text/html; charset=utf-8',
+  '.js': 'text/javascript',
+  '.css': 'text/css',
+  '.json': 'application/json',
+  '.png': 'image/png',
+  '.jpg': 'image/jpeg',
+  '.gif': 'image/gif',
+  '.svg': 'image/svg+xml',
+  '.ico': 'image/x-icon',
+  '.woff': 'font/woff',
+  '.woff2': 'font/woff2',
+  '.ttf': 'font/ttf',
+  '.xlsx': 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
+};
+
+function proxyToBackend(req, res) {
+  const options = {
+    hostname: '127.0.0.1',
+    port: 8000,
+    path: req.url,
+    method: req.method,
+    headers: { ...req.headers, host: '127.0.0.1:8000' },
+  };
+  const proxyReq = http.request(options, (proxyRes) => {
+    res.writeHead(proxyRes.statusCode, proxyRes.headers);
+    proxyRes.pipe(res, { end: true });
+  });
+  proxyReq.on('error', (err) => {
+    console.error('Backend error:', err.message);
+    res.writeHead(502, { 'Content-Type': 'application/json' });
+    res.end(JSON.stringify({ error: 'Backend unavailable' }));
+  });
+  req.pipe(proxyReq, { end: true });
+}
+
+function serveStatic(req, res) {
+  let urlPath = req.url.split('?')[0];
+  let filePath = path.join(DIST_DIR, urlPath === '/' ? 'index.html' : urlPath);
+  const ext = path.extname(filePath).toLowerCase();
+
+  fs.stat(filePath, (err, stats) => {
+    if (!err && stats.isFile()) {
+      const contentType = MIME_TYPES[ext] || 'application/octet-stream';
+      res.writeHead(200, { 'Content-Type': contentType });
+      fs.createReadStream(filePath).pipe(res);
+    } else {
+      // SPA fallback
+      const indexPath = path.join(DIST_DIR, 'index.html');
+      fs.readFile(indexPath, (indexErr, data) => {
+        if (indexErr) {
+          res.writeHead(404);
+          res.end('Not Found');
+        } else {
+          res.writeHead(200, { 'Content-Type': 'text/html; charset=utf-8' });
+          res.end(data);
+        }
+      });
+    }
+  });
+}
+
+const server = http.createServer((req, res) => {
+  if (req.url.startsWith('/api/') || req.url.startsWith('/docs') || req.url === '/openapi.json') {
+    proxyToBackend(req, res);
+  } else {
+    serveStatic(req, res);
+  }
+});
+
+const PORT = process.env.PORT || 3000;
+server.listen(PORT, () => {
+  console.log('DAK Portal running on port ' + PORT);
+});