🎨 Palette: Add aria-hidden to decorative FontAwesome icons

[ErisonBarros]

💡 What: Added `aria-hidden="true"` to raw HTML FontAwesome `` tags.
🎯 Why: To prevent screen readers from reading out the text-based fallbacks (like `:map-marked-alt:`), which creates confusing noise for visually impaired users.
📸 Before/After: Visuals remain unchanged.
♿ Accessibility: Improved screen reader compatibility by explicitly hiding decorative FontAwesome icons.

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PR created automatically by Jules for task 15144002964363219365 started by @ErisonBarros

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