feat(ch390): optimize SPI transfer, MAC fallback, and build settings for V1.0.0

- increase UART DMA/ring buffer sizes for mux traffic
- switch SPI1 to Mode0 with prescaler /2 and align CubeMX settings
- refactor CH390 memory read/write path with chunked SPI read and HAL bulk write
- fallback to hardware MAC when configured MAC is invalid (all-zero)
- add mux frame RTT logs and remove redundant UART1 polling
- update Keil post-build viewer integration and include build viewer artifacts
- update AT manual with all-zero MAC behavior

Drivers/CH390/CH390_Interface.c

@@ -60,6 +60,7 @@ extern SPI_HandleTypeDef hspi1;
 
 /* Timeout for SPI operations (ms) */
 #define SPI_TIMEOUT         100
+#define CH390_SPI_CHUNK_SIZE 64u
 
 /*----------------------------------------------------------------------------
  * Low-level GPIO operations
@@ -105,6 +106,24 @@ static uint8_t ch390_spi_exchange_byte(uint8_t byte)
     return rx_data;
 }
 
+static int ch390_spi_read_bytes(uint8_t *data, uint16_t length)
+{
+    static const uint8_t dummy_tx[CH390_SPI_CHUNK_SIZE] = {0};
+
+    while (length > 0u)
+    {
+        uint16_t chunk = (length > CH390_SPI_CHUNK_SIZE) ? CH390_SPI_CHUNK_SIZE : length;
+        if (HAL_SPI_TransmitReceive(&hspi1, (uint8_t *)dummy_tx, data, chunk, SPI_TIMEOUT) != HAL_OK)
+        {
+            return -1;
+        }
+        data += chunk;
+        length = (uint16_t)(length - chunk);
+    }
+
+    return 0;
+}
+
 static void ch390_spi_apply_mode(uint32_t polarity, uint32_t phase)
 {
     hspi1.Init.CLKPolarity = polarity;
@@ -281,16 +300,15 @@ void ch390_write_reg(uint8_t reg, uint8_t value)
  */
 void ch390_read_mem(uint8_t *data, int length)
 {
-    int i;
-    
+    if (data == NULL || length <= 0)
+    {
+        return;
+    }
+
     ch390_cs(0);                                /* CS low - select */
     ch390_spi_exchange_byte(OPC_MEM_READ);      /* Send memory read command */
-    
-    /* Read data bytes */
-    for (i = 0; i < length; i++)
-    {
-        data[i] = ch390_spi_dummy_read();
-    }
+
+    (void)ch390_spi_read_bytes(data, (uint16_t)length);
     
     ch390_cs(1);                                /* CS high - deselect */
 }
@@ -322,16 +340,15 @@ void ch390_read_mem_dma(uint8_t *data, int length)
  */
 void ch390_write_mem(uint8_t *data, int length)
 {
-    int i;
-    
+    if (data == NULL || length <= 0)
+    {
+        return;
+    }
+
     ch390_cs(0);                                /* CS low - select */
     ch390_spi_exchange_byte(OPC_MEM_WRITE);     /* Send memory write command */
-    
-    /* Write data bytes */
-    for (i = 0; i < length; i++)
-    {
-        ch390_spi_exchange_byte(data[i]);
-    }
+
+    (void)HAL_SPI_Transmit(&hspi1, data, (uint16_t)length, SPI_TIMEOUT);
     
     ch390_cs(1);                                /* CS high - deselect */
 }