feature: added saving graph to json

src/App.tsx

@@ -5,8 +5,10 @@ import type { BreadcrumbItemType } from 'antd/es/breadcrumb/Breadcrumb';
 import { useKeysdownStore } from './stores/ArrayStore';
 import {
   MenuFoldOutlined,
-  MenuUnfoldOutlined
+  MenuUnfoldOutlined,
+  SaveOutlined,
 } from '@ant-design/icons';
+import { saveConceptSketch } from './utils/saveGraph';
 import { useGraphLayersTreeStore } from './stores/TreeStore';
 
 const { Header, Content, Sider } = Layout;
@@ -67,6 +69,18 @@ const App: React.FC = () => {
                   color: colorBgContainer,
                 }}
               />
+              <Button
+                type="text"
+                icon={<SaveOutlined />}
+                onClick={saveConceptSketch}
+                title="Save as JSON"
+                style={{
+                  fontSize: '16px',
+                  width: 32,
+                  height: 32,
+                  color: colorBgContainer,
+                }}
+              />
             </div>
             <Breadcrumb items={graphLevel} />
           </Space>