Fix UART1 GPIO mapping and simplify command logging.

Use TX=GPIO3 and RX=GPIO2 at 921600 to match the terminal adapter wiring;
log received message id and which handler command is triggered.

Co-authored-by: Cursor <cursoragent@cursor.com>

main/uart.h

@@ -6,11 +6,13 @@
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdint.h>
-#define UART_NUM UART_NUM_1
-#define UART_BUF_SIZE 256
-#define UART_TXD_PIN 2
-#define UART_RXD_PIN 3
 
+#define UART_NUM UART_NUM_1
+#define UART_BAUD_RATE 921600
+#define UART_TXD_PIN 3
+#define UART_RXD_PIN 2
+
+#define UART_BUF_SIZE 256
 #define START_MARKER 0xAA
 #define STOP_MARKER 0xCC
 #define MAX_BUF_SIZE 256