The program shell wrappers have been renamed from `ya` to `yy`
following the introduction of the new CLI tool named `ya`.
With this in mind, the `shellWrapperName` option has been introduced
to provide users with more flexibility in choosing the name they're
most accustomed to (ra, lf, ...).
Co-authored-by: XYenon <register@xyenon.bid>
Co-authored-by: 三咲雅 · Misaki Masa <sxyazi@gmail.com>