🎨 Palette: Prevent page scrolling when playing Mario game

[EiJackGH]

💡 What

Updated the mario-game.njk view to call e.preventDefault() on game-related keypresses (Space, Arrow keys). I also restricted the jump action to specifically "Space" or "ArrowUp", rather than any keypress.

🎯 Why

Browsers natively interpret Space and Arrow keys as commands to scroll the page. When playing a browser-based game, this creates a frustrating user experience where the entire game container jumps up and down while the user is trying to play. Additionally, jumping when a user pressed an unrelated key (like 'A' or 'Shift') felt unpolished.

📸 Before/After

(Visuals remain identical, interaction is what changed.)

• Before: Pressing Space would jump Mario AND scroll the page down if the window wasn't perfectly sized. Pressing "A" would jump Mario.
• After: Pressing Space/Arrow keys only affects the game, preventing annoying scrolling. Jumping is restricted to proper jump keys.

♿ Accessibility

Keyboard players can now reliably use the game without interfering with their broader browser viewport or triggering unintended page navigation.

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PR created automatically by Jules for task 5245249649879977107 started by @EiJackGH

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