🎨 Palette: Add focus-visible parity for hover animations

[kuasar-mknd]

💡 What: Added focus-visible parity to multiple elements that previously only had hover animations (e.g., scale or translate). Elements affected include the social icons, the latest posts "Explorer" link, the 404 page back links, and the back-to-top button.
🎯 Why: To provide the same physical and visual feedback (animations, color changes, translations) to keyboard users when tabbing through the interface as mouse users get when hovering over those elements.
📸 Before/After: Before, tabbing to the elements would show a focus ring but lack the playful translations or scaling. Now, keyboard focus triggers the exact same visual cues as hover.
♿ Accessibility: Improved keyboard navigation experience by ensuring consistent visual cues for focus states across interactive elements.

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PR created automatically by Jules for task 17387970059517645804 started by @kuasar-mknd

[google-labs-jules]

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