Add battery sensor to ohme

[dan-r]

Proposed change

Add battery sensor to Ohme. Not too sure on the approach here as the battery is actually for the connected car rather than the device itself...

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request: Will do as part of Add actions section to Ohme home-assistant.io#36598

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
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• The code has been formatted using Ruff (ruff format homeassistant tests)
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

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  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
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[joostlek]

You can use translation keys to mention that this is for the connected vehicle

[joostlek]

Also, if the vehicle is disconnected, what does it show

[dan-r]

Done. When nothing is connected it'll either:

• Still show the up to date battery % - if you've linked the car with the charger in the manufacturers app,
  or
• Show the amount of charge added in the last session - if no car is linked

Either way, its showing what you would get if you looked in the Ohme app, charging or not.

[dan-r]

Oops forgot to update those snapshots. Also changed car to vehicle, seems like a better term as it could be a van/some other vehicle.