🎨 Palette: Improve GameCard accessibility

[Gamepulse]

I have improved the accessibility of the GameCard component by converting non-semantic interactive elements into proper HTML buttons.

💡 What:

• Replaced span role="button" with <button type="button"> for tags, metadata, and status badges.
• Added descriptive aria-label attributes to these buttons.
• Implemented focus-visible:ring-2 styles to ensure clear visual feedback for keyboard users.
• Cleaned up an unused variable in GameScreenshotsCarousel.tsx that was causing build failures.

🎯 Why:
This change makes the game library much more navigable for users who rely on keyboards or screen readers, ensuring that all interactive elements are correctly identified and reachable.

♿ Accessibility:

• Native keyboard support (Enter/Space) via semantic buttons.
• Clearer focus indicators.
• Meaningful ARIA labels for icon-only and badge elements.

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PR created automatically by Jules for task 8158581704525922385 started by @Gamepulse

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