Make the game easier to play for people that struggle with English

[Mikolaj]

See https://www.reddit.com/r/roguelikedev/comments/dgrgmd/ui_issues_dislike_ui_seen_from_english_nonnative/

Most of all, let's enable copy-paste of game text. For now, it only works in the terminal and GTK frontends, both of which are semi-maintained and not comfortable to play for other reasons. With the browser version, perhaps wait until the Canvas re-implementation.