refactor: Change default exports to named exports for consistency

api/health.js

@@ -1,10 +0,0 @@
-// Health check endpoint for Vercel
-module.exports = function handler(req, res) {
-    res.json({
-        status: 'ok',
-        timestamp: new Date().toISOString(),
-        endpoints: {
-            reportError: '/api/report-error'
-        }
-    })
-}