ISSUE 3: add paste functionality

src/components/DockBuilder/DockBuilder.jsx

@@ -523,6 +523,19 @@ export const DockBuilder = () => {
 
   const PasteSelection = () => {
     // TODO: Paste selection
+    if (clipboard) {
+      clipboard.clone(function (clonedObj) {
+        // Offset the pasted object so it's visible
+        clonedObj.set({
+          left: (clonedObj.left || 0) + 20,
+          top: (clonedObj.top || 0) + 20,
+          evented: true,
+        });
+        editorMemo.add(clonedObj);
+        editorMemo.setActiveObject(clonedObj);
+        editorMemo.renderAll();
+      });
+    }
   };
 
   const onDeleteSelection = () => {