auth01: decommission host and remove authelia/lldap services

Remove auth01 host configuration and associated services in preparation
for new auth stack with different provisioning system.

Removed:
- hosts/auth01/ - host configuration
- services/authelia/ - authelia service module
- services/lldap/ - lldap service module
- secrets/auth01/ - sops secrets
- Reverse proxy entries for auth and lldap
- Monitoring alert rules for authelia and lldap
- SOPS configuration for auth01

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

hosts/http-proxy/configuration.nix

@@ -21,8 +21,6 @@
     "prometheus"
     "alertmanager"
     "jelly"
-    "auth"
-    "lldap"
     "pyroscope"
     "pushgw"
   ];