pkg/60171: mpv quickly segfaults when using libcaca video output

["opensauce04%gmail.com@localhost via gnats" <gnats-admin%NetBSD.org@localhost>]

>Number:         60171
>Category:       pkg
>Synopsis:       mpv quickly segfaults when using libcaca video output
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Apr 02 18:45:00 +0000 2026
>Originator:     Daniel
>Release:        NetBSD 11.0_RC2 / pkgsrc 2026Q1
>Organization:
>Environment:
NetBSD netbook.powerhub 11.0_RC2 NetBSD 11.0_RC2 (GENERIC) #0: Wed Mar  4 21:02:00 UTC 2026  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/amd64/compile/GENERIC amd64
>Description:
When attempting to play a video via mpv using the libcaca video option via `mpv --vo=caca <url>`, I receive the following message:

zsh: segmentation fault (core dumped)  mpv --vo=caca <url>

I don't receive this message with the same video when using either the default or tct video output options, so this issue seems specific to the --vo=caca.

libcaca support must be explicitly enabled before building mpv by adding the following to mk.conf:

PKG_OPTIONS.mpv = caca
>How-To-Repeat:
Attempt to play a video with mpv while using the `--vo-caca` option, ensuring that mpv is built with libcaca support.
>Fix: