Add SPI data handling and serialization support

Introduced `SpiParameters` and related structs to process SPI data. Added JSON marshaling/unmarshaling logic and a handler for the "SPI" command in the server. This enables parsing and transforming SPI data effectively for device communication.

cmd/dev-server/main.go

@@ -112,6 +112,18 @@ func handleCameraCoveredAlarm(sPack *n9m.SmartPackage, pack n9m.Package, respons
 	return nil
 }
 
+func handleSPI(_ *n9m.SmartPackage, pack n9m.Package) (err error) {
+	var params n9m.SpiParameters
+
+	if err = pack.GetParametersAs(&params); err != nil {
+		return
+	}
+
+	fmt.Printf("%+v\n", params)
+
+	return
+}
+
 func createSmartPackage(conn net.Conn) (pack *n9m.SmartPackage) {
 	pack = n9m.NewSmartPackage(conn)
 
@@ -120,6 +132,7 @@ func createSmartPackage(conn net.Conn) (pack *n9m.SmartPackage) {
 	pack.AddJSONHandler("CERTIFICATE", "CONNECT", handleCertificateConnect)
 	pack.AddJSONHandler("CERTIFICATE", "KEEPALIVE", handleKeepAlive)
 	pack.AddJSONHandler("CONFIGMODEL", "GET", handleGetConfig)
+	pack.AddJSONHandler("DEVEMM", "SPI", handleSPI)
 
 	pack.AddAlarmHandler(n9m.AlarmTypeMotionDetection, handleUselessAlarms)