New port: sysutils/termdown - an ASCII art countdown timer for the terminal

Hi,

Please find attached the port of sysutils/termdown. Termdown is a
countdown timer (or alternatively a stopwatch) that shows up
prominently in the terminal. It takes a variety of time durations and
absolute time designations to count down to [1]. The email includes
the dependency graphics/py-art which is a python library for terminal
ASCII art in different styles [2].

Proposing this now as a countdown timer can be useful for scheduled
live streams, like for example with obs-studio [3]. After announcing
the stream, the countdown timer can help with signaling the audience
that may have tuned in early that the stream will start at a particular
time.

ok to import?

[1] https://github.com/trehn/termdown
[2] https://pypi.org/project/art/
[3] https://marc.info/?l=openbsd-ports&m=178377397524447&w=2