Fix controls height usage in Select

[Hypnosphi]

The function value wasn't evaluated in Select classnames

[Copilot]

Pull Request Overview

This PR fixes an issue where the controls height value wasn't being properly evaluated in the Select component's CSS class names. The fix extracts the height calculation logic into a reusable method to ensure consistent evaluation across the component.

Key Changes

• Extracted height calculation logic into a private getHeight() method
• Updated CSS class name generation to use the new method instead of inline evaluation
• Applied the same height calculation fix to the _getIcons() method

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