* gnu/services/desktop.scm (seatd-group-sanitizer): New variable.
(<seatd-configuration>)[user]: Removed field.
[group]: Changed to "seat". Sanitize via seatd-group-sanitizer.
(seatd-accounts): New variable.
(seatd-environment): Adjust to <seatd-configuration> ABI.
(seatd-service-type)[extensions]: Add account-service-type with seatd-accounts.
* gnu/tests/desktop.scm (run-minimal-desktop-test): Check for correct
ownership of $SEATD_SOCK.
* doc/guix.texi ("Desktop Services")[seatd-service-type]: Mention that users
may need to become members of the "seat" group.
Update default value for group field.
Add explanation on seatd.sock file.
Remove dropped user field.
d1815a68ea