Add sensor platform to laundrify integration

[xLarry]

Proposed change

This PR adds the sensor platform to the laundrify integration implementing two entities with the following device classes:

• power: showing the latest measurement in Watts
• energy: showing the total consumption in kWh

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: Add sensor platform to laundrify integration home-assistant.io#33596

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.
• I have followed the development checklist
• I have followed the perfect PR recommendations
• 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

If the code communicates with devices, web services, or third-party tools:

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
• For the updated dependencies - a link to the changelog, or at minimum a diff between library versions is added to the PR description.

To help with the load of incoming pull requests:

• I have reviewed two other open pull requests in this repository.

[frenck]

This integration uses a coordinator, shouldn't that be used instead?

[xLarry]

I chose to use a non-coordinated entity for the PowerSensor since the latest power measurements are polled locally from each individual power plug.

Opposed to that, the latest updates for the EnergySensor and BinarySensor are fetched from the backend in a single call (using the LaundrifyUpdateCoordinator).

[frenck]

Why not use a coordinator per device to handle this? As in, that would allow you to use coordinator entities, retry logic, and unavailable logic that is all provided by the datacoordinator.

[xLarry]

My understanding of a coordinator was to group data polling for several entities/devices to a single, coordinated API call.

Using a coordinator per device sounds a bit counter-intuitive to me. As per the developer docs:

If you can map exactly one device endpoint to a single entity, you can fetch the data for this entity inside the update()/async_update() methods.

Let me know if I miss something.

[home-assistant]

Please take a look at the requested changes, and use the Ready for review button when you are done, thanks 👍

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[xLarry]

Hi @frenck,

Thanks for your prompt and thorough review.

I addressed the requested changes in my latest commits, referenced the corresponding commits in a comment and resolved the discussion if applicable.

Some discussions required further information and are left unresolved. Would be great if you could double-check them.

Enjoy your weekend!

// EDIT:
Just pulled the latest changes from dev and rebased this branch (after #121435 has already been merged). Hope I didn't break anything by force-pushing the updated branch.