Add native unit types for weather entities

[rianadon]

Proposed change

I'm attempting to port @emontnemery's addition of native_units to SensorEntity to the WeatherEntity class.

This will allow integrations publishing weather data results to convert their data to local units, without needing to write unit conversion routines in each integration. This can also be used as a base to implement unit conversion for weather templates, like in #48641.

It is very unlikely this change should break custom components. However, I did find one component (met_office) that already defined a visibility_unit method but did not return floats in its visibility method. If any other components pull similar shenanigans, they will break.

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• Dependency upgrade
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• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

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[probot-home-assistant]

Hey there @fabaff, mind taking a look at this pull request as it has been labeled with an integration (weather) you are listed as a code owner for? Thanks!
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[emontnemery]

I think this looks good!

To prevent the @final decorator from breaking CI, don't add it until all existing integrations are updated.

[emontnemery]

Tests are needed too, I just noticed it's missing from sensor tests.
Maybe do something like this: #59546

[rianadon]

I've added a bit more. There are tests, and also as a result of cleaning up unit types the precision of temperature values is no longer set by the integration's units but rather the user's units. So I updated the climacell test to add the precision necessary for Celsius values.

Edit: I'm going to add the precision change in a different PR.

[rianadon]

I'm changing the names of the new methods to no longer have the native_ prefixes in front of them to be more consistent with what we have already. Adding a separate native_temperature also made it difficult to decide whether to use the integration's overridden temperature method or to use the default native_temperature implementation.

Plus, everything gets unit-converted anyways in state_attributes.

[rianadon]

The code should be ready to go now!

[emontnemery]

Thanks, @rianadon 👍

[frenck]

Why is hass config doing the unit conversion?

wind_seed should be imported directly from util.unit_system instead.

The same applies to all other unit conversions happening here.

[frenck]

This PR is causing massive breaking changes.

While I think the idea is good, I think the way it is set up is not fitting nor correct.

For that reason:

• Opened up Revert "Weather units: climacell (1.3/4)" #63842 to revert Weather units: climacell (1.3/4) #61472
• Opened up Revert "Weather units: Buienradar (1.2/4)" #63843 to revert Weather units: Buienradar (1.2/4) #61470

I think it is cool to support unit conversion on an entity or device level in the future, but we cannot rely on core configuration for e.g., unit of mass or pressure. Which unit to use for those cases heavily relies on the use case.