Fixes a weird NodeJS bug

It looks like that from some version NodeJS decided to do localhost requests on IPv6 first instead of IPv4 https://github.com/nodejs/node/issues/40537, so we can't use "localhost" directly any more without changing everything to IPv6.

vite.config.js

@@ -9,7 +9,7 @@ export default defineConfig({
     server: {
         port: 3000,
         proxy: {
-            '/api': 'http://localhost:4000/',
+            '/api': 'http://127.0.0.1:4000/',
         },
     },
     plugins: [preactPlugin()],