🎨 Palette: Ensure animation parity between hover and keyboard focus

[kuasar-mknd]

💡 What:
Added group-focus-visible and group-focus-within Tailwind utility classes to the "ImageGallery" zoom icon and the "LatestPosts" folder icon components to match their existing group-hover animations. Also documented this micro-UX learning in .jules/palette.md.

🎯 Why:
To ensure keyboard-only and screen reader users navigating via Tab receive the same visual feedback (e.g., scaling, rotating, background color changes) as mouse users hovering over interactive elements.

📸 Before/After: Visual parity achieved and verified via Playwright focus screenshot captures locally.

♿ Accessibility:
Ensured the interactive UI states are highly accessible and responsive regardless of the user’s input modality.

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PR created automatically by Jules for task 3820123557017661435 started by @kuasar-mknd

[google-labs-jules]

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