Type conversion errors cause a crash on connect().

I'm using the sample code for this library found here, with no modifications: https://learn.adafruit.com/networking-in-circuitpython/networking-with-the-wifi-module but connections consistently fail with a type conversion error.

The MQTT-specific details of the sample code are:

```python
import adafruit_minimqtt.adafruit_minimqtt as MQTT

# Callback setup removed...

mqtt_client = MQTT.MQTT(
broker=os.getenv("mqtt_broker"),
port=os.getenv("mqtt_port"),
username=os.getenv("mqtt_username"),
password=os.getenv("mqtt_password"),
socket_pool=socketpool.SocketPool(wifi.radio),
ssl_context=ssl.create_default_context(),
)

print("Connecting to MQTT broker...")
mqtt_client.connect()
```

When this code runs, there's a `TypeError` that crashes the script:

```
Traceback (most recent call last):
File "", line 67, in
File "adafruit_minimqtt/adafruit_minimqtt.py", line 448, in connect
File "adafruit_minimqtt/adafruit_minimqtt.py", line 545, in _connect
File "adafruit_connection_manager.py", line 328, in get_socket
TypeError: can't convert str to int
```

For what it's worth my `settings.toml` looks like this:

```
mqtt_broker = 192.168.1.169
mqtt_port = 1883
mqtt_user = "mqttuser"
mqtt_password = ""
```

Mosquitto is running at the broker address above with matching credentials.

I'm using the most recent version of this library (from `adafruit-circuitpython-bundle-10.x-mpy-20260724`), on a Raspberry Pi Pico 2 W.

Reproduce the failure with the sample configuration, then start at connect() and _connect() in adafruit_minimqtt/adafruit_minimqtt.py. Follow the traceback into get_socket() in adafruit_connection_manager.py and compare the values passed from settings.toml. Done means the shown MQTT configuration no longer crashes during connect().

Written by the indexing model from the issue text.