Refactor LabelEdit (#32752)

And fix a regression:
https://github.com/go-gitea/gitea/pull/30053#discussion_r1874405470

Major changes:

* rewrite without jquery
* remove the "delete modal", using "link-action" is good enough
* merge "new modal" and "edit modal"

web_src/js/features/common-organization.ts

@@ -12,5 +12,5 @@ export function initCommonOrganization() {
   });
 
   // Labels
-  initCompLabelEdit('.organization.settings.labels');
+  initCompLabelEdit('.page-content.organization.settings.labels');
 }