v0.4.1

Fixed

• refreshAfterUpgrade now honours its AbortSignal and its timeout while
  asleep. The wait between polls was a bare setTimeout: the signal was only
  read between iterations, so an abort landed up to a full pollInterval late,
  and a pollInterval longer than what remained of timeout ran the method past
  its own deadline. The sleep now wakes the moment the signal fires, the final
  wait is capped to the time left, and no poll starts once the deadline has
  passed. An already-aborted signal makes zero network calls rather than one
  last validate(). The timer is also unref'd on Node/Bun, so a pending poll
  no longer keeps a one-shot script alive.
• README documents requireSignedConfig. The 0.4.0 flag was in the
  changelog and the types but not in the README, whose quick start fetches the
  keyset at runtime with fetchKeyset(...) — the one thing you must not rely on
  once the flag is on. The Configuration Reference now covers the flag (off by
  default; enable only for a product with a trial length configured in the
  dashboard; unverified settings are never cached and the seed is kept) and
  states that enabling it means pinning trustedKeys at build time, because a
  keyset fetched over the same connection as the settings can be forged by the
  same attacker. The KeylightOptions doc comment says the same thing instead
  of claiming the SDK never fetches a keyset.