fix: set vite base to /lead-to-policy/ for path-based preview

vite.config.ts

@@ -3,6 +3,9 @@ import react from '@vitejs/plugin-react';
 import tailwindcss from '@tailwindcss/vite';
 
 // https://vite.dev/config/
-export default defineConfig({
+// Preview is served under /lead-to-policy/ (path-based frontgen preview);
+// local dev stays at / so the running dev server's URL is unaffected.
+export default defineConfig(({ command }) => ({
   plugins: [react(), tailwindcss()],
-});
+  base: command === 'build' ? '/lead-to-policy/' : '/',
+}));