feat(ckeditor5/codeblock): add copy icon

packages/ckeditor5/src/plugins/copy_to_clipboard_button.ts

@@ -0,0 +1,21 @@
+import { ButtonView, Plugin } from "ckeditor5";
+import copyIcon from "../icons/copy.svg?raw";
+
+export default class CopyToClipboardButton extends Plugin {
+
+    public init() {
+        const editor = this.editor;
+        const componentFactory = editor.ui.componentFactory;
+
+        componentFactory.add("copyToClipboard", locale => {
+            const button = new ButtonView(locale);
+            button.set({
+                tooltip: "Copy to clipboard",
+                icon: copyIcon
+            });
+
+            return button;
+        });
+    }
+
+}