Refactor MQTTBridge to utilize FreeRTOS for improved task management and responsiveness

- Moved MQTT processing to a dedicated FreeRTOS task on Core 0, enhancing non-blocking behavior.
- Implemented a FreeRTOS queue for thread-safe packet handling, replacing the previous circular buffer approach.
- Updated WiFi initialization and connection management to occur within the FreeRTOS task, improving overall system responsiveness.
- Enhanced logging and error handling for MQTT connections and packet processing.
- Cached broker and analyzer server statuses to reduce redundant checks and improve efficiency.

examples/simple_repeater/MyMesh.cpp

@@ -1174,11 +1174,11 @@ void MyMesh::handleCommand(uint32_t sender_timestamp, char *command, char *reply
 
 void MyMesh::loop() {
   // Check radio FIRST to ensure we don't miss incoming packets
-  // MQTT processing can take time, so we prioritize radio reception
+  // MQTT processing runs in a separate FreeRTOS task on Core 0, so we don't call bridge.loop() here
   mesh::Mesh::loop();
 
 #ifdef WITH_BRIDGE
-  bridge.loop();
+  // bridge.loop() is now handled by FreeRTOS task on Core 0 - no need to call it here
 #endif
 
   if (next_flood_advert && millisHasNowPassed(next_flood_advert)) {

examples/simple_room_server/MyMesh.cpp

@@ -898,7 +898,7 @@ void MyMesh::loop() {
   // MQTT processing can take time, so we prioritize radio reception
   mesh::Mesh::loop();
 #ifdef WITH_MQTT_BRIDGE
-  bridge.loop();
+  // bridge.loop() is now handled by FreeRTOS task on Core 0 - no need to call it here
 #endif
 
   if (millisHasNowPassed(next_push) && acl.getNumClients() > 0) {

src/helpers/bridges/MQTTBridge.h

@@ -9,6 +9,13 @@
 #include <Timezone.h>
 #include "helpers/JWTHelper.h"
 
+#ifdef ESP_PLATFORM
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+#include <freertos/queue.h>
+#include <freertos/semphr.h>
+#endif
+
 #if defined(MQTT_DEBUG) && defined(ARDUINO)
   #include <Arduino.h>
   // USB CDC-aware debug macros: only print if Serial is ready (non-blocking check)
@@ -96,10 +103,19 @@ private:
   };
   
   static const int MAX_QUEUE_SIZE = 10;
+  
+  // FreeRTOS queue for thread-safe packet queuing
+  #ifdef ESP_PLATFORM
+  QueueHandle_t _packet_queue_handle;
+  TaskHandle_t _mqtt_task_handle;
+  SemaphoreHandle_t _raw_data_mutex;  // Mutex for raw radio data
+  #else
+  // Fallback to circular buffer for non-ESP32 platforms
   QueuedPacket _packet_queue[MAX_QUEUE_SIZE];
   int _queue_head;
   int _queue_tail;
-  int _queue_count;
+  #endif
+  int _queue_count;  // Protected by queue operations or mutex
   
   // NTP time sync
   WiFiUDP _ntp_udp;
@@ -151,6 +167,10 @@ private:
   // Configuration validation state
   bool _config_valid;
   
+  // Cached broker connection status (updated in callbacks to avoid redundant checks)
+  bool _cached_has_brokers;
+  bool _cached_has_analyzer_servers;
+  
   // Throttle logging for disconnected broker messages
   unsigned long _last_no_broker_log;
   static const unsigned long NO_BROKER_LOG_INTERVAL = 30000; // Log every 30 seconds max
@@ -172,6 +192,13 @@ private:
   void connectToBrokers();
   void processPacketQueue();
   bool publishStatus();  // Returns true if status was successfully published
+  
+  // FreeRTOS task function (runs on Core 0)
+  #ifdef ESP_PLATFORM
+  static void mqttTask(void* parameter);
+  void mqttTaskLoop();  // Main loop for MQTT task
+  void initializeWiFiInTask();  // WiFi initialization moved to task
+  #endif
   void publishPacket(mesh::Packet* packet, bool is_tx, 
                      const uint8_t* raw_data = nullptr, int raw_len = 0, 
                      float snr = 0.0f, float rssi = 0.0f);

src/helpers/radiolib/RadioLibWrappers.cpp

@@ -103,7 +103,27 @@ int RadioLibWrapper::recvRaw(uint8_t* bytes, int sz) {
       if (len > sz) { len = sz; }
       int err = _radio->readData(bytes, len);
       if (err != RADIOLIB_ERR_NONE) {
-        MESH_DEBUG_PRINTLN("RadioLibWrapper: error: readData(%d)", err);
+        // Throttle error logging to avoid spam (CRC errors are common in noisy environments)
+        static unsigned long last_crc_error_log = 0;
+        static unsigned long crc_error_count = 0;
+        unsigned long now = millis();
+        crc_error_count++;
+        
+        // Log every 10 seconds max, or on first error
+        if (last_crc_error_log == 0 || (now - last_crc_error_log > 10000)) {
+          MESH_DEBUG_PRINTLN("RadioLibWrapper: error: readData(%d) - %lu errors in last 10s", err, crc_error_count);
+          last_crc_error_log = now;
+          crc_error_count = 0;
+        }
+        
+        // For CRC mismatch errors (-7), reset radio state to prevent stuck conditions
+        // Similar to CustomLR1110's handling of header errors
+        if (err == -7) {  // RADIOLIB_ERR_CRC_MISMATCH
+          // Call standby() to reset radio to known-good state
+          // This helps recover from false packet detections or corrupted state
+          _radio->standby();
+        }
+        
         len = 0;
       } else {
       //  Serial.print("  readData() -> "); Serial.println(len);