🎨 Palette: Add explicit empty state for personal best

[EiJackGH]

💡 What: Added an explicit, encouraging empty state for the "Personal Best" indicator when the user hasn't set a high score yet.
🎯 Why: Previously, the high score was completely hidden if it was 0. Showing an explicit "None yet! Set a record!" message clarifies the system state, introduces the concept of a high score to new users, and encourages engagement.
📸 Before/After: Visual text change in CLI.
♿ Accessibility: N/A - Improves general usability and clarity.

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PR created automatically by Jules for task 16566475145712945038 started by @EiJackGH

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