ansible: asxpio-services is managed by NixOS

With asxpio-services described in nixos/, Ansible only has asxpio-ops
left. Drop the runner, SillyTavern and Minecraft roles, the services
host from both inventories, and the WireGuard client play.

The s3fs role and playbook go as well: the mounts were switched off on
asxpio-ops, and on asxpio-services nothing read them. The credentials
file the role once wrote on asxpio-ops stays, because the backup script
there reads it.

site.yaml against asxpio-ops still changes nothing.

Assisted-by: Claude:fable-5-2

ansible/inventory/hosts.yaml

@@ -1,6 +1,7 @@
 ---
 # Default inventory: run from a workstation over WireGuard, as root.
 # CI uses inventory/ci.yaml instead (VPC addresses, user deploy).
+# asxpio-services runs NixOS and is not managed by Ansible; see ../nixos.
 
 all:
   vars:
@@ -14,7 +15,3 @@ all:
           hosts:
             asxpio-ops:
               ansible_host: "{{ wireguard_ip }}"
-        services_servers:
-          hosts:
-            asxpio-services:
-              ansible_host: "{{ wireguard_ip }}"