78379d244f
Add three new fields to support the snapshot/live streaming protocol phase: - snapshotPhase: Boolean (true during initial snapshot) - pendingEvents: List<ServerMessage> (FIFO buffer during snapshot) - cursors: Map<String, Long> (per-session high-water marks for deduplication) All fields include KDoc documenting their invariants and purpose. Additive change only; all existing tests continue to pass.