bump: bud@6.12.0 & improvements (#3128)

This PR contains various improvements and cleanups to the configuration and JavaScript code. Key changes include:

- Adding simple comments to `jsconfig.json`.
- Improving config: `bud.wpjson.set` replaces `bud.wpjson.settings`. Note that `bud.wpjson.settings` is not deprecated.
- `bud.wpjson.settings` now disables `dropCap` by default.
- `app.js` and `editor.js` now use `if (import.meta.webpackHot)` instead of optional chaining, since `import.meta.webpackHot` is not a real method and using optional chaining might cause errors.

resources/scripts/editor.js

@@ -16,4 +16,4 @@ domReady(() => {
 /**
  * @see {@link https://webpack.js.org/api/hot-module-replacement/}
  */
-import.meta.webpackHot?.accept(console.error);
+if (import.meta.webpackHot) import.meta.webpackHot.accept(console.error);