fix: yet more wiznet bugs, reconnects, led status indicators

lib/ioLibrary_Driver/MQTT/MQTTClient.h

@@ -48,7 +48,14 @@
 enum QoS { QOS0, QOS1, QOS2 };
 
 /* all failure return codes must be negative */
-enum returnCode { BUFFER_OVERFLOW = -2, FAILURE = -1, SUCCESSS = 0 };
+enum returnCode { 
+    NO_DATA = -100,          /* No data available (timeout) */
+    PROTOCOL_ERROR = -4,     /* Invalid packet type or format */
+    DECODE_ERROR = -3,       /* Failed to decode packet length */
+    BUFFER_OVERFLOW = -2,    /* Buffer too small */
+    FAILURE = -1,           /* Generic failure */
+    SUCCESS = 0 
+};
 
 /* The Platform specific header must define the Network and Timer structures and functions
  * which operate on them.