[Feature Request]: Add option for customisable idle message

[NaiveInvestigator]

Similiar to this script:
https://github.com/9beach/mpv-config/blob/main/scripts/modernx-and-quotes.lua

sosc will read from a text file and choose a random line as a message. The reason for doing in this way is that the user can add their own quotes which will be used to display on the idle screen.

Finally the idle screen is a tad less boring now.

Hope you consider this!