Correct state/device class for water in gardena

[elupus]

Use water instead of volume to ensure this is allowable in energy dashboard and make sure we add measurement state class where applicable.

Proposed change

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• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• This PR fixes or closes issue: fixes #
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[elupus]

If it applies cleanly to last release it would be good to pick it, but no bigie if it's delayed.

[Copilot]

Pull request overview

This PR updates the Gardena Bluetooth integration’s water-related sensors so they use the correct sensor device/state classes, aligning them with Home Assistant’s water/energy dashboard validation rules.

Changes:

• Switch flow total sensors from SensorDeviceClass.VOLUME to SensorDeviceClass.WATER.
• Add SensorStateClass.MEASUREMENT where applicable (flow rate and spray distance).
• Update snapshot expectations to reflect the new device/state class metadata.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
homeassistant/components/gardena_bluetooth/sensor.py	Corrects water-related sensor metadata (device_class/state_class) for proper classification and statistics behavior.
tests/components/gardena_bluetooth/snapshots/test_sensor.ambr	Updates snapshot outputs to match the new sensor capabilities/attributes.

[erwindouna]

Thanks @elupus!