fix: prevent filter dropdown from opening when disabled

[tmccoy14]

Summary

• Filter Dropdown: Fixed the disabled state — the disabled prop was only applied to the inner Button, so the dropdown still opened on click/keyboard because Radix's DropdownMenuTrigger has its own open handlers. Passing disabled to the trigger now short-circuits those handlers so the menu won't open when disabled.
• Section Heading: Changed the heading prop type from string to React.ReactNode so it can accept a badge alongside the heading text (used for issued credentials).

Changes

• filter-dropdown.tsx — pass disabled to DropdownMenuTrigger in addition to the Button.
• section-heading.tsx — widen heading prop type to React.ReactNode.

Testing

• Verified a disabled FilterDropdown no longer opens via click or keyboard, while the enabled state is unchanged.
• Verified SectionHeading accepts both plain text and a text + Badge combination.