attempt to optimize vite bundling

vite.config.ts

@@ -3,5 +3,40 @@ import { sveltekit } from '@sveltejs/kit/vite';
 import { defineConfig } from 'vite';
 
 export default defineConfig({
-	plugins: [tailwindcss(), sveltekit()]
+	plugins: [tailwindcss(), sveltekit()],
+	optimizeDeps: {
+		// Pre-bundle heavy deps to avoid dev slowdowns
+		include: [
+			'libphonenumber-js',
+			'country-state-city',
+			'phosphor-svelte',
+			'@internationalized/date'
+		],
+		// Exclude problematic deps from pre-bundling
+		exclude: ['moment']
+	},
+	build: {
+		rollupOptions: {
+			output: {
+				manualChunks(id) {
+					// Split heavy phone/location libraries
+					if (id.includes('libphonenumber-js') || id.includes('country-state-city')) {
+						return 'vendor-phone';
+					}
+					// Split Phosphor icons (likely heavy)
+					if (id.includes('phosphor-svelte')) {
+						return 'vendor-icons';
+					}
+					// Split moment if used
+					if (id.includes('moment')) {
+						return 'vendor-date';
+					}
+					// Group other vendor libraries
+					if (id.includes('node_modules')) {
+						return 'vendor';
+					}
+				}
+			}
+		}
+	}
 });