fix(runtime): use jQuery, not bare $, in the lazily loaded clipboard lib

WordPress runs jQuery in noConflict mode, so bare $ is undefined. The
clipboard module called $(this) on every click and $.isFunction on the
copy result, so any click on a [data-clipboard-text] button threw
"$ is not a function" and copied nothing.

This was latent: the only prior emitter was the paid card, and the click
path only ran when a user actually clicked it. Exposing the copy button on
the download box made it reachable on every resource, surfacing the error.

Bind through jQuery explicitly, guard notyf so a missing toast lib cannot
also throw, and drop the _win.bd dependency (that payload only gains .bd
once main.js runs). Contract-lock the module under simulated noConflict.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

assets/js/runtime/libs/clipboard.js

@@ -38,14 +38,14 @@ function copyText(text, success, error, _this) {
     }
 }
 
-_win.bd.on('click', "[data-clipboard-text]", 'clipboard', function (e) {
-    var _this = $(this);
+window.jQuery('body').on('click', "[data-clipboard-text]", 'clipboard', function (e) {
+    var _this = jQuery(this);
     var text = _this.attr('data-clipboard-text');
     var tag = _this.attr('data-clipboard-tag') || '内容';
 
     copyText(text, function () {
-        notyf(tag + "已复制")
+        typeof notyf === 'function' && notyf(tag + "已复制")
     }, function () {
-        notyf(tag + "复制失败，请手动复制", 'danger')
+        typeof notyf === 'function' && notyf(tag + "复制失败，请手动复制", 'danger')
     }, this);
 })