🎨 Palette: Add accessibility attributes to SectionEditor buttons

[aafre]

💡 What: Added type="button", ARIA labels, semantic role="img" wrappers for emojis, and explicit keyboard focus states (focus-visible) to the inline buttons inside SectionEditor.
🎯 Why: To ensure screen reader users understand the purpose of the icon-only buttons (save/cancel) and to provide clear visual feedback for keyboard navigation.
📸 Before/After: Visual change is subtle (addition of focus rings when navigating via keyboard), but screen reader experience is vastly improved.
♿ Accessibility: Added aria-label to buttons missing text content, wrapped emojis in aria-hidden spans, added type="button" to prevent accidental form submission behavior, and added focus-visible classes to all interactive buttons in the component.

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PR created automatically by Jules for task 13363041532025596295 started by @aafre

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[gemini-code-assist]

Code Review

This pull request improves accessibility and keyboard navigation in the SectionEditor component by adding explicit button types, ARIA labels, wrapping emoji icons in accessible spans, and applying focus-visible ring styles. The review feedback correctly identifies a critical issue where React state is mutated directly using .splice() on a nested array, and provides an actionable, immutable alternative using map and filter.

[gemini-code-assist]

Directly mutating React state by using .splice() on a nested array reference (updatedSections[sectionIndex].content) can prevent React from detecting state changes and trigger unexpected rendering behavior. Instead, update the state immutably using map and filter.

                type="button"
                aria-label="Remove item"
                onClick={() => {
                  const updatedSections = sections.map((sec, idx) => {
                    if (idx !== sectionIndex) return sec;
                    return {
                      ...sec,
                      content: sec.content.filter((_: any, i: number) => i !== itemIndex),
                    };
                  });
                  setSections(updatedSections);
                }}
                className="bg-red-500 text-white px-3 py-1 rounded hover:bg-red-600 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-offset-2 focus-visible:ring-red-500"