x11-wm/twm: Update to 1.0.13.1

Add WWW and update pkg-descr.

https://lists.x.org/archives/xorg-announce/2025-May/003599.html
https://lists.x.org/archives/xorg-announce/2025-May/003600.html

PR: 287157
Approved by: x11 (arrowd)
Approved by: fluffy (mentor)