Behavior-preserving; 231 BattleNode tests green.
One enum conflated two axes. Split:
- HandshakePhase (per participant): AwaitingInitNetwork..AfterReady. On
IHasHandshakePhase.Phase, FrameDispatchContext.SenderPhase, the handler gates.
- SessionLifecycle (per battle): Active | Terminal. On the renamed
BattleSessionState.Lifecycle (was SessionPhase, defaulting to a handshake value)
and BattleSession.Lifecycle (was Phase). Reads are only != Terminal, so the
Active default is behavior-identical.
OpponentTurn was dead (never assigned) -> dropped. BattleSessionPhase deleted; the
two axes can no longer be cross-assigned.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
