v2.1.0

• Snapshot generation age is checked continuously, including while the transport stays online. Old payloads in a
  receive backlog cannot keep advancing remote replay after its delay/prediction budget is exhausted. This holds
  the declared playback time and retains histories; it does not invent missing movement or hide present-position lag.

• GameClient.receiveState / StateReceiver: shared reconnect recovery for authoritative snapshot streams. It
  resets or retains application histories by policy, holds playback through offline and online-without-fresh-data
  phases, and accepts recovery only after a usable current-connection snapshot on the selected stream. New sessions
  always reset. Idle snapshot headers can release recovery; rejected deltas, queued old state and unrelated streams
  cannot. Raw callbacks and wire protocol 4 are unchanged. The party example uses the shared receiver.

• AdaptivePlayback.updateDelay(dtMs) separates delay adaptation from cursor movement. The receiver learns valid
  recovery-header lateness while holding its cursor, so a slower new route can recover without advancing old state.

• A proven RTC recovery now clears retry backoff, so an intermittent network outage does not inherit debt from an
  earlier recovered outage. Duplicate rtc-reset controls for an already-stopped attempt no longer increase that
  debt. This changes no wire bytes or application API. The native gate repeats three recoveries and injects duplicate
  resets; OS-level one-way UDP checks also retain their original failing observation and the candidate rerun.

• Queued traffic on a socket retired by session takeover is ignored, including a repeated hello. It cannot reclaim
  the player or produce misleading new protocol errors while its close is still in flight. Unauthenticated binary
  traffic on a new connection remains rejected.