- AudioEvent: add speaker_id field (was on VoiceFrame only; needed on all events)
- ToneEvent: add session_id field for session correlation across embedded consumers
- README: full wire format documentation — JSON shape, field reference table,
SSE envelope, Elcor mode subtext table, module license map
- ToneEvent docstring references cf-core#40 as the wire format spec
Closes cf-core#40