[wayland] seatd VT switching and device access for wlroots-based programs

The common/terminal.c changes are just a minor cleanup for consistency
with the FreeBSD code, I suspect the current port would work just as
well.

The hopefully more useful part of the diff: using the rc script and
the instructions in the README I get working VT switching both from
the wayland/greetd prompt and from a "startxfce4 --wayland" session
using labwc. If you're using greetd please test with the diff I sent
earlier today. For some reason startcagebreak.sh appears to error out
and go back to the greetd prompt. Hopefully the debugging
instructions in the README will prove useful. I haven't tested other
compositors.

It would be tempting to add a _seatd group instead of telling users to
add a local one, but well, it wouldn't remove the need for explicit
configuration steps and we're short on uids/gids (tm).

Thoughts? ok?


Index: Makefile
===================================================================
RCS file: /cvs/ports/sysutils/seatd/Makefile,v
diff -u -p -r1.9 Makefile
--- Makefile 19 Oct 2025 08:27:21 -0000 1.9
+++ Makefile 2 Jan 2026 13:39:31 -0000
@@ -1,6 +1,7 @@
COMMENT = minimal seat management daemon and universal library

V = 0.9.1
+REVISION = 0
DISTNAME = seatd-$V
CATEGORIES = sysutils

Index: patches/patch-common_terminal_c
===================================================================
RCS file: /cvs/ports/sysutils/seatd/patches/patch-common_terminal_c,v
diff -u -p -r1.3 patch-common_terminal_c
--- patches/patch-common_terminal_c 19 Oct 2025 08:27:21 -0000 1.3
+++ patches/patch-common_terminal_c 2 Jan 2026 13:52:16 -0000
@@ -16,14 +16,23 @@ Index: common/terminal.c
#else
#error Unsupported platform