File Explorer II

Requirements

• Render the supplied arbitrary-depth tree in sibling order using nested treeitems and groups. All folders start collapsed; no file is selected.
• Name the outer role=tree element Project files. Each node uses role=treeitem, data-node and its name as aria-label. Nested children must be direct treeitems inside a role=group owned by their parent.
• Only folders have aria-expanded; use true or false, including empty folders. Files omit aria-expanded and expose aria-selected based on the selected full path.
• Native buttons toggle folders or select files. Display the selected full path in the status output; folders do not change selection. Preserve descendant expansion when an ancestor is reopened.
• Keep the supplied dataset and IDs. This stage focuses on structural semantics and native button access; complete tree-widget arrow navigation and type-ahead are outside its scope. Basic indentation CSS is supplied.

Examples

Input: Open src, then components, and select Button.js
Output: Show nested child groups and the selected path src/components/Button.js.

Input: Close src and reopen it
Output: The components folder remains expanded.