ssot_target_host now prefers the env-scoped internalDomains host over the
public domains host, so the Stage-2 (U5) serviceRef assertion expects demo
backends' OPENAI_BASE_URL/etc. to point at
http://showcase-aimock.railway.internal:4010 (free intra-env networking)
rather than the billed public egress host. Non-aimock targets (no
internalDomains) fall back to their public host unchanged.
Red-green: reverting the resolver makes the three new U5 tests fail (public
host asserted); restoring makes them pass. Full Ruby spec suite green (184
runs, 715 assertions, 0 failures).
Jordan Ritter
91cd2d8118