🎨 Palette: Improve Accessibility and Dropzone UX

[Nawayisus]

🎨 Palette: Improve Accessibility and Dropzone UX

💡 What: Added ARIA for attributes to form labels linking to their <select> elements, fully enabled keyboard interactivity (focus, Enter/Space key triggers) on the file #dropZone, and added aria-live and aria-valuenow attributes to the progress area.
🎯 Why: Makes the core application workflow navigable for screen readers and keyboard-only users, turning the static dropzone into a truly accessible button pattern while preventing event bubbling loops.
📸 Before/After: Visuals verified via Playwright screenshot.
♿ Accessibility: High impact form control associations, screen reader progress announcements, and keyboard dropzone support.

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PR created automatically by Jules for task 11765848328117986172 started by @Nawayisus

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