distant: remove extra file

distant/brain/brain.go

@@ -4,4 +4,4 @@ type Interface interface {
 	Think(prefix []string) (string, error)
 }
 
-func Think(s Interface, prompt string) (string, error) { panic("TODO") }
+func Think(br Interface, prompt string) (string, error) { panic("TODO") }

distant/brain/types.go

@@ -1,6 +0,0 @@
-package brain
-
-type (
-	Message struct{}
-	Tuple   struct{}
-)