Improve BLE scan reliability for BMS selection

firmware/esp32/xterra-controller/bms.cpp

@@ -85,6 +85,9 @@ int scanBleDevices(uint32_t scanSeconds) {
         Serial.println("BLE: Disconnecting BMS before scan");
         client->disconnect();
         bmsData.connected = false;
+
+        Serial.println("BLE: Waiting for device advertising...");
+        delay(2000);
     }
 
     bleScanResultCount = 0;

firmware/esp32/xterra-controller/xterra-controller.ino

@@ -356,7 +356,7 @@ void handleDebugSerial() {
     }
 
     if (command == "scan ble") {
-        int count = scanBleDevices(10);
+        int count = scanBleDevices(20);
 
         if (count == 0) {
             Serial.println("No BLE devices found.");