use tree kind for relation types menu item

src/Umbraco.Web.UI.Client/src/backoffice/settings/relation-types/menu-item/manifests.ts

@@ -1,15 +1,15 @@
-import type { ManifestMenuItem } from '@umbraco-cms/backoffice/extensions-registry';
+import type { ManifestTypes } from '@umbraco-cms/backoffice/extensions-registry';
 
-const menuItem: ManifestMenuItem = {
+const menuItem: ManifestTypes = {
 	type: 'menuItem',
+	kind: 'tree',
 	alias: 'Umb.MenuItem.RelationTypes',
 	name: 'Relation Types Menu Item',
 	weight: 40,
-	loader: () => import('./relation-types-menu-item.element'),
 	meta: {
+		treeAlias: 'Umb.Tree.RelationTypes',
 		label: 'Relation Types',
 		icon: 'umb:folder',
-		entityType: 'relation-type',
 	},
 	conditions: {
 		menus: ['Umb.Menu.Settings'],

src/Umbraco.Web.UI.Client/src/backoffice/settings/relation-types/menu-item/relation-types-menu-item.element.ts

@@ -1,40 +0,0 @@
-import { html, nothing } from 'lit';
-import { customElement, state } from 'lit/decorators.js';
-import { UmbLitElement } from '@umbraco-cms/internal/lit-element';
-
-@customElement('umb-relation-types-menu-item')
-export class UmbRelationTypesMenuItemElement extends UmbLitElement {
-	@state()
-	private _renderTree = false;
-
-	private _onShowChildren() {
-		this._renderTree = true;
-	}
-
-	private _onHideChildren() {
-		this._renderTree = false;
-	}
-
-	// TODO: check if root has children before settings the has-children attribute
-	// TODO: how do we want to cache the tree? (do we want to rerender every time the user opens the tree)?
-	// TODO: can we make this reusable?
-	render() {
-		return html`<umb-tree-item
-			label="Relation Types"
-			icon="umb:folder"
-			entity-type="relation-type"
-			@show-children=${this._onShowChildren}
-			@hide-children=${this._onHideChildren}
-			has-children>
-			${this._renderTree ? html`<umb-tree alias="Umb.Tree.RelationTypes"></umb-tree>` : nothing}
-		</umb-tree-item> `;
-	}
-}
-
-export default UmbRelationTypesMenuItemElement;
-
-declare global {
-	interface HTMLElementTagNameMap {
-		'umb-relation-types-menu-item': UmbRelationTypesMenuItemElement;
-	}
-}