[3.15] gh-151678: Add interactive tests for tkinter.simpledialog (GH-151794) (GH...

[3.15] gh-151678: Add interactive tests for tkinter.simpledialog (GH-151794) (GH-151802)

Drive the modal query dialogs with generated events to exercise the
<Return> and <Escape> key bindings and the value validation: accepting
an integer, float or string, cancelling, rejecting a non-numeric value
and rejecting a value outside the allowed range.
(cherry picked from commit 706238e764169dd36f918a0541adf9687cc3f296)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>