The relay adapter re-attaches an egress discriminator on outbound replies
so the connector can resolve the owning tenant. It captured scope_id for
scoped (guild) messages and user_id for DMs, but as MUTUALLY EXCLUSIVE:
a scoped inbound hit an early return, so the author's user_id was never
recorded, and _with_scope only attached user_id when there was no
scope_id. Guild replies therefore went out with scope_id only.
That's fine while the guild has a provision-time route row. But a MANAGED
Discord agent joins guilds dynamically (the shared bot is added to /
removed from servers at runtime), and GATEWAY_RELAY_ROUTE_KEYS — the only
thing that writes guild route rows — is a self-hosted, static field never
stamped for managed agents. So their guild has no route row, the
connector's guild-route lookup misses, and with no user_id on the frame
there's nothing to fall back to → every guild reply is declined
"discord egress declined: target not routed to an onboarded tenant"
even though INBOUND resolved the same guild fine (via the author-first
SharedSocketRouter.targets() fallback).
Fix: capture the authentic author user_id for EVERY inbound (DM and
scoped alike) and re-attach it on the outbound reply alongside scope_id.
The connector consults it only on a route/scope miss, so carrying both
never overrides routing-table resolution. This is the gateway half of the
paired gateway-gateway change (makeDiscordTenantOf guild-route-miss
author-binding fallback); together they make guild replies resolve the
same observed-author way inbound already does.
Tests (tests/gateway/relay/test_relay_adapter.py): a guild reply now
carries both scope_id AND user_id; a scoped inbound with no author still
yields scope_id only (never invents one). Verified fail-without /
pass-with.