chore: add helper to clear vditor cache

frontend/src/utils/clearVditorStorage.js

@@ -0,0 +1,7 @@
+export function clearVditorStorage() {
+  Object.keys(localStorage).forEach(key => {
+    if (key.startsWith('vditoreditor-') || key === 'vditor') {
+      localStorage.removeItem(key)
+    }
+  })
+}