Proposed change

When a user changes the entity_id of enabled entity, that has not been loaded yet, the old restored state not cleaned up. This can cause issues with integrations like MQTT that can have entities in the entity registry that are not loaded (yet). After the entity has been renamed (e.g. via the UI or via discovery, the change cannot be reverted, because the old restored state is still loaded after renaming). This PR cleans up the old entity state in case the old entity had a restored state during a rename of the entity_id and sets an unavailable state to the entity with the new ID.

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: Can't change MQTT entity's ID via HA UI #150400
• Link to documentation pull request:
• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

• The code change is tested and works locally.
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• Tests have been added to verify that the new code works.

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