🎨 Palette: Add accessibility value to node_modules collapsible section

[acebytes]

💡 What: Added an .accessibilityValue to the node_modules section header button to announce whether it is expanded or collapsed.
🎯 Why: Custom buttons acting as collapsible sections rely entirely on visual cues (like a chevron icon changing direction). VoiceOver users would previously only hear the text without knowing the state of the collapsible section. Adding an explicit .accessibilityValue ensures that screen reader users receive auditory feedback about the expanded/collapsed state, making the interface more accessible.
📸 Before/After: Visuals remain unchanged; this is an accessibility improvement for VoiceOver users.
♿ Accessibility: The node_modules section header now announces "Expanded" or "Collapsed" when focused via VoiceOver, providing missing state information.

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PR created automatically by Jules for task 1205040186161186134 started by @acebytes

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