Update postinstall.sh for NC25

# Add VHOST_ACCOUNTS from .env file as a system config value, to be used by our ecloud-accounts plugin

docker-compose exec -T --user www-data nextcloud php occ config:system:set e_welcome_domain --value="welcome.$DOMAIN"

echo "Performing some Nextcloud administrative tasks"

# Add missing indices

docker-compose exec -T --user www-data nextcloud php /var/www/html/occ db:add-missing-indices

# Set default domain

docker exec -u www-data nextcloud /var/www/html/occ config:system:set main_domain --value $DOMAIN

docker exec -u www-data nextcloud /var/www/html/occ config:system:set legacy_domain --value $DOMAIN

docker-compose exec -T --user www-data nextcloud php occ maintenance:mode --off

# define all default preview providers AND the video preview provider, now that ffmpeg is bundled in the image