Restrict launches to prepared runtimes (Refs #93)

src/lib/server/provisioning/native.ts

@@ -136,7 +136,7 @@ export function nativeLaunchSelection(
             throw new Error('The selected host is being removed. Choose another host.');
     }
     // Only the controller-configured default may be prepared automatically.
-    // Custom runtimes must already be present in trusted host inventory; a
+    // Custom runtimes must be reported as admin-prepared by the host agent; a
     // launch request must never authorize a registry download.
     if (
         image !== config.defaultRuntimeImage &&
@@ -144,7 +144,7 @@ export function nativeLaunchSelection(
             (host) =>
                 !host.decommission &&
                 (automatic ? host.mode === 'active' : host.id === input.hostId) &&
-                host.inventory.runtimeImages?.includes(image)
+                host.inventory.preparedRuntimeImages?.includes(image)
         )
     ) {
         throw new Error(