gofmt rackctl.go

CI's gofmt step failed on it since a9ca326, so CI and the deploy that
follows it stopped running.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

cmd/rollcall/rackctl.go

@@ -42,7 +42,7 @@ type RackController struct {
 	Name           string      `json:"name"`
 	URL            string      `json:"url"`               // how machines reach it, e.g. http://10.213.78.1
 	TLSURL         string      `json:"tls_url,omitempty"` // the same host over HTTPS, when it serves it (agents)
-	Kind           string      `json:"kind"` // embedded | remote
+	Kind           string      `json:"kind"`              // embedded | remote
 	Version        string      `json:"version"`
 	Arch           string      `json:"arch,omitempty"` // GOARCH, for self-update
 	Interfaces     []RackIface `json:"interfaces"`