feat(machine): add OS and kernel version information to machine info, show in 'machine ls'

internal/machine/osinfo/osinfo_other.go

@@ -0,0 +1,8 @@
+//go:build !linux
+
+package osinfo
+
+// KernelVersion returns an empty string on non-Linux hosts where the machine daemon does not run.
+func KernelVersion() string {
+	return ""
+}