🎨 Palette: Add dynamic ARIA labels to icon-only settings toggles

[endlessblink]

🎨 Palette: Accessibility improvements for Settings icon-only buttons

💡 What: Added dynamic aria-label attributes to several icon-only toggle buttons within the Application Settings modals.
🎯 Why: To improve accessibility for screen reader users. Previously, the password visibility toggle, API key visibility toggle, and token copy buttons lacked descriptive labels, making it difficult for visually impaired users to understand their function or current state. The new dynamic labels (e.g., "Show password" vs. "Hide password") provide immediate, accurate context based on the button's active state.
♿ Accessibility: Enhances screen reader navigation by ensuring interactive controls have clear, context-aware accessible names.

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PR created automatically by Jules for task 992476351577107368 started by @endlessblink

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