The peer range was capped at ^0.3.0, so once Kafka reached 0.4.0 no application
depending on both packages could upgrade — `npm ci` failed with ERESOLVE naming
this package's peerOptional as the blocker. The reference app hit it the moment
it adopted Kafka 0.5.0 for request-reply; the cap was stale, not protective.

Isolated review of the widened range: those Kafka releases are additive, and the
surfaces this package uses — KafkaProducerService.send, the consumer decorators,
KafkaContext — are unchanged across all three. Verified against 0.5.0 rather
than assumed: 135 tests, 100% coverage, the complexity gate, both samples, and
the Kafka sample's typecheck all green.

Releases 0.5.2. No code changed — peer range, sample pins, and the version
surfaces only.