unibilium: add ncurses as build input

unibilium expects to use the `ncursesw6-config` command to find terminfo dirs. Before that would fail & default to some nonexistant TERMINFO_DIRS value (on pure systems at least). This will add `ncurses.out` which is a little bit unfortunate because unibilium is meant as a replacement for ncurses. In the future, we should add a `terminfo` output to ncurses so that other things can use its db without pulling in its libraries & binaries.

Fixes #40404.