It is excessive control to manually configure the terminal height limit
just for stats, if anything this should be added as an option used all
throughout mpv.
Use the property introduced in bf025cd289 to clip the lines of stats.lua
with accurate unicode width detection and considering --msg-module and
--msg-time. This allows removing the term ellipsis functions.
Also use script-opts-append instead of script-opts in the docs so
script-opts in mpv.conf, which could change keybindings, are not
overriden.