beb7941236
The #94219 replay was a production no-op: the server returned full JSON-RPC envelopes from session.events.since while the client's replay loop dispatches only elements with a top-level 'type' — every replayed event was silently skipped. Each side's tests validated its own assumption, so both suites stayed green. - server: events_since() now returns bare event objects (the frame's params), the exact shape the live dispatch path consumes; ring stores params directly; cross-language contract test added on both sides. - client: live frames racing an in-flight replay are parked and flushed seq-gated afterward — no double dispatch of deltas, no gap-skip from a watermark advanced past the replay window. - restart poisoning: seq counters are in-process, so a backend restart reset them while clients kept high watermarks (replay forever empty, truncated=false). New replay_epoch advertised in gateway.ready and echoed by session.events.since; the client clears watermarks on epoch change. - methods_session no longer reaches into event_replay privates (is_truncated() accessor). Live repro: pre-fix, 3 stamped frames -> 0 dispatchable by the client gate; post-fix 3/3. Tests: 16 py (replay+ws), 8 vitest, tsc clean, ruff clean.