🎨 Palette: Add encouraging empty state for high score

[EiJackGH]

💡 What: Added an explicit, encouraging empty state message when a user's high score is 0.
🎯 Why: Hiding UI elements when data is empty leaves users guessing about system state, especially first-time users. Explicit, encouraging empty states clarify what goes there and improve onboarding.
📸 Before/After: N/A (Text-based CLI change)
♿ Accessibility: Improves cognitive accessibility by providing clear feedback about system state for first-time users.

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PR created automatically by Jules for task 4803990671190757693 started by @EiJackGH

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