sculpt: use secondary CPU for leitzentrale

By decoupling the leitzentrale from the (contended) boot CPU, the fading
on F12 interferes much less with animations like nano3d deployed in the
runtime.

Fixes #3268

repos/gems/run/sculpt.run

@@ -33,6 +33,8 @@ install_config {
 		<service name="VM"/>
 	</parent-provides>
 
+	<affinity-space width="2" height="1"/>
+
 	<default-route>
 		<any-service> <parent/> <any-child/> </any-service>
 	</default-route>
@@ -370,6 +372,7 @@ install_config {
 	<start name="leitzentrale" caps="4000" priority="-2">
 		<binary name="init"/>
 		<resource name="RAM" quantum="164M"/>
+		<affinity xpos="1" width="1"/> <!-- decouple leitzentrale from boot CPU -->
 		<provides> <service name="Nitpicker"/> </provides>
 		<route>
 			<service name="LOG"> <child name="log"/> </service>