Instead of typing into the combobox, find the toggle button ("^" icon) in the
same container as the tooth input and click it via JS to open the dropdown.
Tries progressively wider ancestor scopes (1-5 levels up) to locate the button,
falls back to JS focus if none found. Then selects the exact tooth number from
the listbox options.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>