voice.go is still the biggest file in cmd/mavend and most of what is left
has nothing to do with the audio path. The ecosystem integration is one
such lump: it talks to Nexus, Praxis and Hexis over HTTP and only touches
the handler for its store and clock. Lifting it into ecosystem_acts.go
puts it next to ecosystem.go, where the clients it drives already live.
Move-only: handlePraxisAct, recordPraxisTrace (called from nowhere else),
handleHexisAct and execHexis verbatim, plus the two imports that became
unused in voice.go.
kami