debug: add heap integrity checkpoints

firmware/esp32/overland-controller/overland-controller.ino

@@ -1,4 +1,5 @@
 #include <WiFi.h>
+#include <esp_heap_caps.h>
 #include <WebServer.h>
 #include <Preferences.h>
 #include <esp_wifi.h>
@@ -1631,7 +1632,9 @@ bool startAccessPoint() {
 void restartAccessPoint() {
     WiFi.softAPdisconnect(true);
     delay(250);
+    heapCheckpoint("before:startAccessPoint");
     startAccessPoint();
+    heapCheckpoint("after:startAccessPoint");
 }
 
 void sendSimpleJsonError(int status, const char* error, const char* detail) {
@@ -2085,7 +2088,9 @@ void connectStaWifi() {
 
         WiFi.disconnect(false, false);
         delay(500);
+        heapCheckpoint("before:WiFi.mode");
     WiFi.mode(WIFI_AP_STA);
+    heapCheckpoint("after:WiFi.mode");
         delay(250);
 
         WiFi.begin(staSsids[i].c_str(), staPasswords[i].c_str());
@@ -3115,7 +3120,9 @@ void handleDebugSerial() {
     }
 
     if (command == "config") {
+        heapCheckpoint("before:printConfig");
     printConfig();
+    heapCheckpoint("after:printConfig");
         return;
     }
 
@@ -4070,8 +4077,28 @@ void handleStatus() {
     server.send(200, "application/json", output);
 }
 
+
+void heapCheckpoint(const char* label) {
+    Serial.print("HEAP CHECK ");
+    Serial.print(label);
+    Serial.print(" free=");
+    Serial.print(ESP.getFreeHeap());
+    Serial.print(" min=");
+    Serial.println(ESP.getMinFreeHeap());
+
+    if (!heap_caps_check_integrity_all(true)) {
+        Serial.print("HEAP CORRUPTION DETECTED AT: ");
+        Serial.println(label);
+        while (true) {
+            delay(1000);
+        }
+    }
+}
+
 void setup() {
     Serial.begin(115200);
+    delay(500);
+    heapCheckpoint("setup:start");
 
 #if DASHBOARD_UART_ENABLED
     DashboardSerial.begin(
@@ -4088,23 +4115,37 @@ void setup() {
     Serial.println("Overland Controller Booting");
     Serial.println("==================================");
 
+    heapCheckpoint("before:oledBegin");
     oledBegin();
+    heapCheckpoint("after:oledBegin");
 
+    heapCheckpoint("before:loadConfig");
     loadConfig();
+    heapCheckpoint("after:loadConfig");
     printConfig();
 
     pinMode(IGNITION_PIN, INPUT);
 
+    heapCheckpoint("before:initRelays");
     initRelays();
+    heapCheckpoint("after:initRelays");
+    heapCheckpoint("before:initSensors");
     initSensors();
+    heapCheckpoint("after:initSensors");
 #if BMS_COMPILE_ENABLED
+    heapCheckpoint("before:initBms");
     initBms();
+    heapCheckpoint("after:initBms");
 #else
     Serial.println("BMS/BLE disabled for LilyGO bring-up test");
 #endif
 
+    heapCheckpoint("before:loadWifiConfig");
     loadWifiConfig();
+    heapCheckpoint("after:loadWifiConfig");
+    heapCheckpoint("before:loadApConfig");
     loadApConfig();
+    heapCheckpoint("after:loadApConfig");
 
     WiFi.mode(WIFI_AP_STA);
     startAccessPoint();
@@ -4226,9 +4267,12 @@ void setup() {
     });
 
 
+    heapCheckpoint("before:server.begin");
     server.begin();
+    heapCheckpoint("after:server.begin");
 
     Serial.println("Web Server Started");
+    heapCheckpoint("setup:end");
 }
 
 void loop() {