🎨 Palette: Improve dynamic score accessibility

[EiJackGH]

💡 What: Extracted dynamic game score value into a dedicated aria-live region separated from the static 'Score:' text.
🎯 Why: Ensures screen readers can accurately and politely announce dynamic score updates during gameplay without redundantly repeating the static label text.
📸 Before/After: Visual presentation is identical, but underlying DOM is distinct.
♿ Accessibility: Drastically improves screen reader experience for users tracking their game progress in real-time.

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PR created automatically by Jules for task 15559299365126802987 started by @EiJackGH

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