gh-151910: Add tkinter.ttk.Treeview methods for the Tk 9.1 enhanced treeview (GH...

gh-151910: Add tkinter.ttk.Treeview methods for the Tk 9.1 enhanced treeview (GH-151911)

Wrap the enhanced ttk::treeview widget commands added in Tk 9.1 (TIP 740),
and the detached query added in Tk 9.0, as tkinter.ttk.Treeview methods:
item navigation and queries (after_item, before_item, depth, haschildren,
visible, size, range, identifier, current), opening, hiding, sorting and
searching (expand, collapse, hide, unhide, sort, search, search_all,
search_cell, search_all_cells), cell focus, selection and tagging
(cellfocus, cellselection and its set/add/remove cell-list and *_range
rectangle forms, anchor/includes/present, tag_cell_add/remove/has), and the
detached query (detached, detached_all).

The expand() and collapse() methods, without recurse, also work on Tk older
than 9.1, where they are emulated via the item -open option.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>