Add system service status to operational data

[rical]

Description

Add information about system services and their status to sysrepo operational data. This is the base for showing the information in various front ends, such as CLI or Web.

Finit information will be the origin of the data, here's how it looks from initctl.

PID   IDENT       STATUS   RUNLEVELS     DESCRIPTION                                  
1185  udevd       running  [S-12345-789] Device event daemon (udev)
2244  dbus        running  [S-123456789] D-Bus message bus daemon
3136  confd       running  [S-12345----] Configuration daemon
3608  netopeer    running  [--12345----] NETCONF server
2825  dnsmasq     running  [S-12345----] DHCP/DNS proxy
3630  tty:hvc0    running  [--12345-789] Getty on hvc0
2826  iitod       running  [S0123456789] LED daemon
3631  klishd      running  [---2345----] CLI backend daemon
3695  mdns-alias  running  [---2345----] mDNS alias advertiser 
0     mstpd       stopped  [S0123456789] Spanning Tree daemon
3635  rauc        running  [---2345----] Software update service
0     resolvconf  done     [S-12345----] Update DNS configuration
3543  statd       running  [S-12345----] Status daemon
3724  staticd     running  [---2345----] Static routing daemon
2241  syslogd     running  [S0123456789] System log daemon
2242  watchdogd   running  [S0123456789] System watchdog daemon
3673  zebra       running  [---2345----] Zebra routing daemon
3694  mdns        running  [---2345----] Avahi mDNS-SD daemon
3696  chronyd     running  [---2345----] Chrony NTP v3/v4 daemon
3704  lldpd       running  [---2345----] LLDP daemon (IEEE 802.1ab)
3706  nginx       running  [---2345----] Web server
3707  rousette    running  [--12345----] RESTCONF server
3712  sshd        running  [---2345----] OpenSSH daemon

This will require the addition of service info to Yang models, preferably in infix-services@2024-12-03.yang .

Example of how it can be displayed in the frontend:

$ show service
nginx - Web server is running
sshd  - OpenSSH daemon is running

$ show service ssh
OpenSSH daemon is running

login: admin
passwrod: ***********

Warning OpenSSH daemon (sshd) has crashed.

Additional Information

No response

General Information

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