fix(app): dismiss the composer track panel when a row is chosen

Track pills became menu surfaces when the trackers moved out of stacked
cards, but ComposerTrackRow kept the raw Pressable it had as an inline
card row. Nothing in that path reaches selectItem, so the popover or
sheet stayed parked over the transcript after opening a subagent, and on
iOS the action fired while UIKit was still tearing the sheet down. Rows
now hand the press to the engine and take closeOnSelect, as MenuItem
does; bulk archive opts out because its progress lands in the panel.

The running mark is the shared StatusRing rather than a still dot the
pill drew for itself, and the remaining dots read their colour from the
one bucket-to-colour map. The slot is sized for the ring in every state
so the label does not step sideways when the last child finishes.

Mounting the real menu engine in a test needed harness work: stubs for
two packages that ship untranspiled Flow, reanimated left out of Vite's
prebundle so its .web files win, and the gaps filled in the unistyles
test theme.

docs/menus.md

@@ -37,6 +37,12 @@ and it loses. Selections used to be dropped entirely for exactly that reason.
 The consequence for callers: an `onSelect` on iOS runs a beat after the press. Don't add a second
 delay on top of it, and don't read state that the same press mutated.
 
+This is why a row inside a menu surface goes through `selectItem` rather than calling its handler
+from its own `Pressable`. `MenuItem` is not the only row shape on the engine — `ComposerTrackRow`
+is another, with its own icons and hover-revealed actions — but both hand the press to the engine
+and take `closeOnSelect` to say whether choosing them ends the surface. A row that owns its press
+outright leaves the surface open behind whatever it opened, and skips the iOS wait.
+
 ## Pages
 
 A submenu is a page, declared as data on the surface and reached by a `MenuSubTrigger` whose `id`