add shell count info for start of round

serve/dto.go

@@ -26,3 +26,9 @@ type Player struct {
 	// Cuffs is whether the player is currently wearing cuffs.
 	Cuffs bool `json:"cuffs,omitempty"`
 }
+
+// ShellCounts is the JSON DTO for shell counts emitted at the start of a round.
+type ShellCounts struct {
+	Live  int `json:"live"`
+	Blank int `json:"blank"`
+}