TreeView (#725)

* feat(tree-view): add TreeView

* fix(tree-view): select initial active node, correct typedefs

* docs(tree-view): update examples

* chore(tree-view): add test for types

* docs(tree-view): rename example

* docs(tree-view): improve docs

* docs(tree-view): refine examples

* docs: fix invalid syntax

* chore: rebuild component index/api

* docs(layout): increase height of sidenav menu [ci skip]

types/TreeView/TreeView.d.ts

@@ -0,0 +1,63 @@
+/// <reference types="svelte" />
+import { SvelteComponentTyped } from "svelte";
+
+export type TreeNodeId = string | number;
+
+export interface TreeNode {
+  id: TreeNodeId;
+  text: string;
+  icon?: typeof import("carbon-icons-svelte").CarbonIcon;
+  disabled?: boolean;
+  expanded?: boolean;
+}
+
+export interface TreeViewProps
+  extends svelte.JSX.HTMLAttributes<HTMLElementTagNameMap["ul"]> {
+  /**
+   * Provide an array of children nodes to render
+   * @default []
+   */
+  children?: Array<TreeNode & { children?: TreeNode[] }>;
+
+  /**
+   * Set the current active node id
+   * Only one node can be active
+   * @default ""
+   */
+  activeId?: TreeNodeId;
+
+  /**
+   * Set the node ids to be selected
+   * @default []
+   */
+  selectedIds?: TreeNodeId[];
+
+  /**
+   * Specify the TreeView size
+   * @default "default"
+   */
+  size?: "default" | "compact";
+
+  /**
+   * Specify the label text
+   * @default ""
+   */
+  labelText?: string;
+
+  /**
+   * Set to `true` to visually hide the label text
+   * @default false
+   */
+  hideLabel?: boolean;
+}
+
+export default class TreeView extends SvelteComponentTyped<
+  TreeViewProps,
+  {
+    select: CustomEvent<TreeNode & { expanded: boolean; leaf: boolean }>;
+    toggle: CustomEvent<TreeNode & { expanded: boolean; leaf: boolean }>;
+    focus: CustomEvent<TreeNode & { expanded: boolean; leaf: boolean }>;
+    keydown: WindowEventMap["keydown"];
+  },
+  { labelText: {} }
+> {}