add audio support, trying to manage MSD device

http/reqrsp/nanokvm.go

@@ -0,0 +1,17 @@
+package reqrsp
+
+const MsgSuccess = "success"
+
+type NanoKVMRsp struct {
+	Code int    `json:"code"`
+	Msg  string `json:"msg"`
+	Data any    `json:"data"`
+}
+
+type FilesRsp struct {
+	Files []string `json:"files"`
+}
+
+type FileRsp struct {
+	File string `json:"file"`
+}