🎨 Palette: [UX improvement] Add ARIA labels to chat inputs and task action buttons

[thirdeyenation]

💡 What: Added aria-label attributes to icon-only action buttons in the tasks list (Info, delete_sweep, close) and the chat input textarea.
🎯 Why: Improves screen reader accessibility for users relying on assistive technologies to understand the purpose of these interactive elements.
📸 Before/After: N/A (No visual changes)
♿ Accessibility: Improves element labeling for screen readers.

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PR created automatically by Jules for task 2620292151861117257 started by @thirdeyenation

[google-labs-jules]

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