(#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.

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

assets/js/datasource/RsvDataSource.js

@@ -1,4 +1,4 @@
-const RsvDataSource = {
+export const RsvDataSource = {
   create_rsv_resource(base_url, { nonce } = {}) {
     function request(url, method, body) {
       const headers = { 'Content-Type': 'application/json' };