feat: add incus auto-client certificate trust (#406)

- add fact to export vault public cert from agents
- add fact to export list of trusted incus client certs
- add method for incus clients to export their client cert to be trusted

Reviewed-on: #406

modules/incus/manifests/init.pp

@@ -92,5 +92,10 @@ class incus (
         }
       }
     }
+
+    # Collect exported client certificates and manage trust
+    Incus::Client_cert <<| tag == 'incus_client' |>> {
+      require => Service['incus'],
+    }
   }
 }