fix: use type-only export for LabelFlyoutItem to fix build error (#2607)

* fix: use type-only export for LabelFlyoutItem to fix build error

LabelFlyoutItem is a TypeScript interface and should be exported as a type-only export.
Exporting it as a value causes build tools (Rollup, Vite, etc.) to fail because
the value does not exist at runtime.

* style: fix formatting issues caught by  CI (#2607)

Author: coririri

plugins/continuous-toolbox/src/index.ts

@@ -11,7 +11,8 @@
 import * as Blockly from 'blockly/core';
 
 import {ContinuousCategory} from './ContinuousCategory';
-import {ContinuousFlyout, LabelFlyoutItem} from './ContinuousFlyout';
+import {ContinuousFlyout} from './ContinuousFlyout';
+import type {LabelFlyoutItem} from './ContinuousFlyout';
 import {ContinuousMetrics} from './ContinuousMetrics';
 import {ContinuousToolbox} from './ContinuousToolbox';
 import {RecyclableBlockFlyoutInflater} from './RecyclableBlockFlyoutInflater';