Add unit tests for Qualia App Switch component

[augmentcode]

Problem

The Switch component in the Qualia frontend was missing unit tests.

Solution

Added a comprehensive test suite in qualia/frontend/src/components/ui/__tests__/switch.test.tsx covering:

• Basic rendering and data-slot attributes.
• Size variants (default and sm).
• Component states (checked, unchecked, disabled, invalid).
• User interactions (click, keyboard space) and onCheckedChange callbacks.
• Accessibility (ARIA roles and labels).

Testing

• Ran tests via vitest: 20 tests passed.

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Pull Request opened by Augment Code | View session

[augmentcode]

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[augmentcode]

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