feat(gui): Add link deletion and DAG cycle validation to Visual DAG

temp_edit4.py

@@ -0,0 +1,20 @@
+with open('src/gui_2.py', 'r', encoding='utf-8', newline='') as f:
+    content = f.read()
+
+old = '''    imgui.end_popup()
+   if self.show_script_output:'''
+
+new = '''    imgui.end_popup()
+   # Cycle Detected Popup
+   if imgui.begin_popup_modal("Cycle Detected!", None, imgui.WindowFlags_.always_auto_resize)[0]:
+    imgui.text_colored(imgui.ImVec4(1, 0.3, 0.3, 1), "The dependency graph contains a cycle!")
+    imgui.text("Please remove the circular dependency.")
+    if imgui.button("OK"):
+     imgui.close_current_popup()
+    imgui.end_popup()
+   if self.show_script_output:'''
+
+content = content.replace(old, new)
+with open('src/gui_2.py', 'w', encoding='utf-8', newline='') as f:
+    f.write(content)
+print('Done')