Bugfix: Actually allow usage of Selector instances for object selector fields

[EuleMitKeule]

Breaking change

Proposed change

This fixes an issue with ObjectSelector instances. The tests for this selector indicate that it should be possible to use an instance of another selector for a field of the object selector. This didn't actually work/broke in some recent version of HASS (at least not for the kinds of selectors I use in my custom integrations inside object selectors).

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:
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[Copilot]

Pull request overview

This PR fixes a bug in the ObjectSelector validation logic where it failed to handle Selector instances directly in field configurations. The ObjectSelector supports both dictionary-based selector configs and Selector instances (as shown in the type definition and tests), but the validation code in __call__ only handled dictionary configs. This resulted in a TypeError when trying to call the selector() function on a Selector instance.

Key Changes

• Modified the __call__ method in ObjectSelector to check if the field selector is already a Selector instance before attempting to instantiate it
• Added type-based branching to handle both Selector instances and dictionary configurations