`limactl ls` should verify for "Running" instances that the process is still alive

#124 showed an example of the qemu process no longer running, and I just experienced the same after a reboot.

It looks like `store.Inspect` is already supposed to detect this (and set the status to "Broken"), but for some reason it doesn't seem to work:

```console
$ l ls
NAME STATUS SSH ARCH DIR
default Running 127.0.0.1:60022 x86_64 /Users/jan/.lima/default
$ l delete -f default
INFO[0000] Sending SIGKILL to the QEMU process 51073
ERRO[0000] no such process
INFO[0000] Sending SIGKILL to the host agent process 51072
ERRO[0000] no such process
INFO[0000] Removing *.pid *.sock under "/Users/jan/.lima/default"
INFO[0000] Removing "/Users/jan/.lima/default/ga.sock"
INFO[0000] Removing "/Users/jan/.lima/default/ha.pid"
INFO[0000] Removing "/Users/jan/.lima/default/qemu.pid"
INFO[0000] Removing "/Users/jan/.lima/default/qmp.sock"
INFO[0000] Removing "/Users/jan/.lima/default/serial.sock"
INFO[0000] Removing "/Users/jan/.lima/default/ssh.sock"
INFO[0000] Deleted "default" ("/Users/jan/.lima/default")
```