The pill trigger paints its own label spans and mounts no SelectValue,
and Radix's item-aligned placement silently skips all positioning when
the value node is absent — the open menu laid out below the
height-locked app shell, fully off-viewport, which reads as a dead
control. The mood and type/source pills on the mood and measurements
lists were affected since the unified filter rail landed in v1.16.1.
Popper placement has no value-node dependency and anchors the menu
under the pill like the date-range popover next to it.