🎨 Palette: Expand clickable area for category rows

[acebytes]

💡 What:

• Wrapped the entire CategoryRow's HStack contents inside a single Button.
• Applied .contentShape(Rectangle()) so empty space is clickable.
• Maintained existing styling by using .buttonStyle(.plain).
• Grouped VoiceOver elements via .accessibilityElement(children: .combine).
• Replaced the nested checkbox button with an Image tied to the row button's action.

🎯 Why:
Previously, users had to click the tiny checkbox icon to select or deselect a category. Expanding the hit area to the entire row makes the interaction significantly more pleasant and forgiving.

📸 Before/After:
Visually identical, but the entire row now reacts to taps/clicks instead of just the leading icon.

♿ Accessibility:
By combining the row elements, VoiceOver now reads the category name, size, risk level, and its selection state cohesively in a single sweep instead of fragmenting it into multiple separate focus elements.

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PR created automatically by Jules for task 2651412343508475026 started by @acebytes

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