5. Filters Toolbar Dropdown UI

[MitchellShiell]

Goal
When multiple filter categories are configured a single filter dropdown is rendered with labelled sections for each key and checkboxes each value. Active selections are reflected with a checked state.

Behaviour Detail

• If only one filter category is configured, the button renders with that category's label rather than the generic "Filters" label
• Checkboxes within a category are multi-select
• The control is disabled in the loading and error states, consistent with other toolbar controls

Figma Link