Add STATUS column in service ls

[miekg]

% ./uc ls
AME              MODE         REPLICAS   IMAGE                                                 STATUS        ENDPOINTS
caddy             global       2          registry.science.ru.nl/cncz/sys/image/caddy:v0.1.35   2/2 healthy   (custom Caddy config)
caddy-extra       replicated   1          registry.science.ru.nl/cncz/sys/image/debug:v0.1.14   1/1 healthy   (custom Caddy config)
caddy-redis       replicated   1          redis:8.4-alpine                                      1/1 healthy
discourse-db      replicated   1          discourse/postgres:latest                             1/1 healthy
discourse-redis   replicated   1          redis:latest                                          1/1 healthy
discourse-web     replicated   1          discourse/discourse:latest                            0/1 healthy   https://discourse-web.web.u.science.ru.nl → :80, https://discourse.science.ru.nl → :80
ip                replicated   1          php:8.1-fpm-alpine                                    1/1 healthy   (custom Caddy config)
ip-data           replicated   1          ip/ip-data:2026-07-20-071158.e7380b2.dirty            1/1 healthy
unkey             global       2          registry.science.ru.nl/cncz/sys/image/unkey:v0.1.44   2/2 healthy

This supersedes #362