🎨 Palette: Add accessibility and tooltips to NodeModulesSection header

[acebytes]

💡 What: Added accessibility labels, values, traits, and a help tooltip to the collapsible NodeModulesSection header.
🎯 Why: To clearly indicate to VoiceOver users that the header acts as an expandable/collapsible button and report its current state. The tooltip provides mouse hover context.
📸 Before/After: Visuals remain unchanged, but VoiceOver now correctly reads the button state and label, and hovering over the area shows a tooltip.
♿ Accessibility: Added accessibilityLabel, accessibilityValue, accessibilityAddTraits, and help modifiers.

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PR created automatically by Jules for task 13643687145363839748 started by @acebytes

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