🎨 Palette: Add explicit label associations for layer filters

[d3mocide]

💡 What: Added explicit htmlFor attributes to <label> elements and matching id attributes to their nested <input> checkboxes across LayerFilters.tsx, LayerVisibilityControls.tsx, and SystemSettingsWidget.tsx.

🎯 Why: While wrapping an input inside a label creates an "implicit" association that is technically valid HTML, adding the explicit id/htmlFor mapping is a highly recommended accessibility best practice. It ensures maximum compatibility with older or less capable screen readers and assistive technologies that sometimes struggle with implicit labels alone.

📸 Before/After: This is an invisible DOM change, no visual updates.

♿ Accessibility: Enhanced screen-reader robustness for the numerous custom toggles in the map layer filters and settings widgets.

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PR created automatically by Jules for task 14909401266047224618 started by @d3mocide

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