Add KNX DALI Gateway Module and Message Queue Implementation

- Introduced KnxDaliModule class for handling DALI message queuing, commissioning, and KNX group-object dispatch.
- Implemented Message and MessageQueue classes for managing message operations.
- Removed obsolete OpenKNX IDF component files and CMake configurations.
- Updated submodule reference for KNX.

Signed-off-by: Tony <tonylu@tony-cloud.com>

components/gateway_knx/include/gateway_knx_internal.h

@@ -0,0 +1,61 @@
+#pragma once
+
+// Internal header shared between gateway_knx.cpp and gateway_knx_router.cpp.
+
+#include "driver/uart.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/semphr.h"
+#include "soc/uart_periph.h"
+
+#include <cstdint>
+#include <string>
+
+namespace gateway {
+namespace knx_internal {
+
+constexpr const char* kTag = "gateway_knx";
+
+// RAII semaphore guard.
+class SemaphoreGuard {
+ public:
+  explicit SemaphoreGuard(SemaphoreHandle_t semaphore) : semaphore_(semaphore) {
+    if (semaphore_ != nullptr) {
+      xSemaphoreTake(semaphore_, portMAX_DELAY);
+      locked_ = true;
+    }
+  }
+  ~SemaphoreGuard() {
+    if (locked_) {
+      xSemaphoreGive(semaphore_);
+    }
+  }
+ private:
+  SemaphoreHandle_t semaphore_{nullptr};
+  bool locked_{false};
+};
+
+// Resolve a UART IO pin from config or SoC defaults.
+inline bool ResolveUartIoPin(uart_port_t uart_port, int configured_pin,
+                             uint32_t pin_index, int* resolved_pin) {
+  if (resolved_pin == nullptr) return false;
+  if (configured_pin >= 0) {
+    *resolved_pin = configured_pin;
+    return true;
+  }
+  if (uart_port < 0 || uart_port >= SOC_UART_NUM ||
+      pin_index >= SOC_UART_PINS_COUNT) {
+    *resolved_pin = UART_PIN_NO_CHANGE;
+    return false;
+  }
+  const int default_pin =
+      uart_periph_signal[uart_port].pins[pin_index].default_gpio;
+  if (default_pin < 0) {
+    *resolved_pin = UART_PIN_NO_CHANGE;
+    return false;
+  }
+  *resolved_pin = default_pin;
+  return true;
+}
+
+}  // namespace knx_internal
+}  // namespace gateway