feat(hostd): varlink interfaced host controller to manage machine configuration and boot mgmt

hostd/src/main.rs

@@ -31,7 +31,9 @@ impl VarlinkInterface for PatagiaHostd {
                     value: "quz".to_string(),
                 },
             ]),
-            patagiaAgent: None,
+            patagiaAgent: Some(PatagiaAgentConfig {
+                url: None, // Some("https://cdn.patagia.dev/patagia-agent/stable".to_string()),
+            }),
         };
         call.reply(machine)
     }