Add suggested_area to MQTT discovery

[RadekHvizdos]

Proposed change

This adds suggested_area to MQTT discovery, so that the discovered devices could be automatically added to the proper area.

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)
• 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: Update documentation MQTT suggested_area home-assistant.io#17003

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
• The code has been formatted using Black (black --fast 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.
• Untested files have been added to .coveragerc.

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[homeassistant]

Hi @RadekHvizdos,

It seems you haven't yet signed a CLA. Please do so here.

Once you do that we will be able to review and accept this pull request.

Thanks!

[probot-home-assistant]

Hey there @emontnemery, mind taking a look at this pull request as its been labeled with an integration (mqtt) you are listed as a codeowner for? Thanks!
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[PeteBa]

I really like this PR - maybe this suggestion is for a different PR - but I notice that entities can also be assigned to areas. They default to the area of the device but they can also be specifically assigned to a differnt area. Is assigning entity areas something that could be supported via mqtt discovery as well?

[emontnemery]

Suggested change

suggested_area="default_area",

Remove this. Instead, add it to DEFAULT_CONFIG_DEVICE_INFO_ID and DEFAULT_CONFIG_DEVICE_INFO_MAC, and update test helpers help_test_entity_device_info_with_identifier + help_test_entity_device_info_with_connection to make sure it works.

[RadekHvizdos]

Thanks for the suggestion, the tests were adjusted accordingly.

[emontnemery]

@PeteBa No, that's not possible as there's no concept of suggested_area for entities.

[emontnemery]

Thanks, @RadekHvizdos for a solid 1st PR 👍