fix: Improve logging - fix LOG_LEVEL filter, reduce HTTP noise

- Fix LOG_LEVEL filtering logic (was inverted)
- HTTP logs now only show errors (4xx, 5xx) by default
- Add database connection check at startup
- Cron jobs logged on separate lines
- LOG_LEVEL=debug shows all HTTP requests

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/index.js

@@ -1,11 +1,25 @@
 import app from './app.js';
 import { startAllCronJobs } from './cron/index.js';
 import { logger } from './utils/logger.js';
+import { testConnection } from './config/database.js';
 
 const port = process.env.PORT || 5000;
-app.listen(port, () => {
-  logger.info(`Server running on http://localhost:${port}`);
 
-  // Start cron jobs after server is running
-  startAllCronJobs();
-});
+const start = async () => {
+  try {
+    // Test database connection
+    await testConnection();
+    logger.success('Database connected');
+
+    // Start server
+    app.listen(port, () => {
+      logger.info(`Server running on http://localhost:${port}`);
+      startAllCronJobs();
+    });
+  } catch (error) {
+    logger.error('Failed to start server', error);
+    process.exit(1);
+  }
+};
+
+start();