(#1) - WebPack bundling of JS and CSS (#1)

This work was done with Claude.

Added bundling of CSS & JS with WebPack. This also means minimization.

---------

Co-authored-by: Martin Slachta <martin.slachta@outlook.com>
Reviewed-on: #1

assets/js/forms/RsvFormEncoder.js

@@ -1,4 +1,4 @@
-const RsvFormEncoder = {
+export const RsvFormEncoder = {
   // Serialize form element into a plain JS object supporting arrays.
   // - Nested keys supported with dot notation: 'meta.email'
   // - Array notation supported with trailing [] (e.g. 'times[]') or multiple inputs with same name