u

server.js

@@ -232,7 +232,7 @@ app.get('/api/history', (req, res) => {
         }
 
         const stmt = db.prepare(`
-            SELECT timestamp, temp_c, humidity, vpd, fan_speed, on_speed 
+            SELECT timestamp || 'Z' as timestamp, temp_c, humidity, vpd, fan_speed, on_speed 
             FROM readings 
             WHERE dev_name = ? AND port = ? AND timestamp >= datetime('now', ?)
             ORDER BY timestamp ASC
@@ -252,6 +252,12 @@ app.get('/api/history', (req, res) => {
 const devMiddleware = webpackDevMiddleware(compiler, {
     publicPath: '/',
     writeToDisk: false,
+    headers: (req, res, context) => {
+        // Set cache headers for hashed bundle files (immutable)
+        if (req.url && req.url.match(/\.[a-f0-9]{8,}\.(js|css)$/i)) {
+            res.setHeader('Cache-Control', 'public, max-age=31536000, immutable');
+        }
+    }
 });
 app.use(devMiddleware);