API returns hardcoded UPS data when no UPS is connected

Description

The GraphQL API returns hardcoded/fake UPS data when querying upsDevices even when no UPS device is actually connected to the system.

Steps to Reproduce

1. Have apcupsd installed but no UPS device connected
2. Query the upsDevices GraphQL endpoint

Expected Behavior

The API should return an empty array [] or indicate that no UPS is available.

Actual Behavior

The API returns:

{
  "data": {
    "upsDevices": [
      {
        "id": "ups1",
        "name": "My UPS",
        "model": "APC Back-UPS Pro 1500",
        "status": "COMMLOST",
        "battery": {
          "chargeLevel": 100,
          "estimatedRuntime": 3600,
          "health": "Good"
        },
        "power": {
          "inputVoltage": 120.5,
          "outputVoltage": 120.5,
          "loadPercentage": 25
        }
      }
    ]
  }
}

Impact

Client applications display a phantom UPS card with fake data ("My UPS" / "APC Back-UPS Pro 1500") to users who don't actually have a UPS device connected.

Thank you!

Start by searching the TypeScript GraphQL implementation of the upsDevices endpoint and the integration with apcupsd. Reproduce the no-UPS condition, then trace why the sample values such as "My UPS" are returned. Done means the query returns an empty array or clearly indicates that no UPS is available when no device is connected.