fix(a11y): 🎨 Palette: Improve screen reader accessibility for inputs and decorative text

[myarichuk]

💡 What: Wrapped decorative trailing arrows in <span aria-hidden="true"> and added descriptive aria-labels to their parent a tags on the Home and Grimoire pages. Added an aria-label to the search input on the Players page.
🎯 Why: Screen readers were reading "rightwards arrow" for the links, confusing the context. Also, inputs without explicit labels need an aria-label as placeholder text is insufficient for screen readers.
♿ Accessibility: Improved screen reader announcements for text links with decorative characters and improved form input accessibility.

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PR created automatically by Jules for task 9127116708966729192 started by @myarichuk

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