e8a1cc82ff
The dropdown was clipped by parent containers using overflow, transform, or stacking context via shadow-sm + z-index combinations. Adopts the same fixed-position strategy as PersonMultiSelect: binds to the input element, computes position via getBoundingClientRect(), and registers svelte:window scroll/resize listeners to keep it current. Also adds full ARIA combobox pattern (role=combobox, aria-expanded, aria-haspopup, aria-controls, aria-activedescendant) and keyboard navigation (ArrowDown/Up, Enter, Escape) matching TagInput's reference implementation. Removes the now-dead z-30/z-10 z-index workarounds from ConversationFilterBar. Closes #343 Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>