Using `insert` plugin breaks grouping rules

[Vexcited]

• Framework: Vue.js 3.5 (Composition API)
• I use dragAndDrop() (from @formkit/drag-and-drop/vue) since I provide my own state

With insert

plugins: [
    insert({
        insertPoint: () => {
            const div = document.createElement('div');
            div.classList.add('control-sorting-indicator');
            return div;
        },
    }),
]

Enregistrement.de.l.ecran.2025-07-04.085920.mp4

As you can see, I can apparently move the elements outside of my group!
It should not work this way, each category have its own dragAndDrop and we should not be able to drag between the groups.

Without insert()

Enregistrement.de.l.ecran.2025-07-04.090220.mp4

As you can see, I am NOT able to drag the elements to the other group and no error is thrown.

[Vexcited]

Seems related to #149