Back off BMS reconnect attempts

firmware/esp32/overland-controller/bms.cpp

@@ -19,6 +19,10 @@ static size_t responseLength = 0;
 static bool responseReady = false;
 
 static unsigned long lastReadAttempt = 0;
+
+static unsigned long lastBmsConnectAttempt = 0;
+static unsigned long bmsConnectBackoffMs = 30000;
+static int bmsConnectFailCount = 0;
 static unsigned long bmsReconnectPausedUntil = 0;
 static bool bmsSetupMode = false;
 static const unsigned long READ_INTERVAL_MS = 5000;
@@ -517,8 +521,31 @@ void updateBms() {
 
     lastReadAttempt = millis();
 
-    if (!connectBms()) {
+    if (!client || !client->isConnected()) {
-        return;
+        unsigned long now = millis();
+
+        if (now - lastBmsConnectAttempt < bmsConnectBackoffMs) {
+            bmsData.connected = false;
+            return;
+        }
+
+        lastBmsConnectAttempt = now;
+
+        if (!connectBms()) {
+            bmsData.connected = false;
+            bmsConnectFailCount++;
+
+            if (bmsConnectFailCount >= 3) {
+                bmsConnectBackoffMs = 60000;
+            } else {
+                bmsConnectBackoffMs = 30000;
+            }
+
+            return;
+        }
+
+        bmsConnectFailCount = 0;
+        bmsConnectBackoffMs = 30000;
     }
 
     if (requestPacket(JBD_STATUS_REQUEST, sizeof(JBD_STATUS_REQUEST))) {