f0ea1ca553
CI / build (push) Failing after 2m8s
Adds adapter-owned externalEventId extraction to the ChannelAdapter contract (WebhookAdapter→eventId, EmailAdapter→Message-ID) and uses it in InboundService, so email replays dedup on Message-ID (previously only payload.eventId worked). Adds an email-dedup spec + smoke-email.mjs proving inbound → normalized, a reply joins the same email thread, bad signature rejected, and outbound EMAIL SENT. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>