afc909fd3b
The capture sanitizer redacted tokens/device ids but left the lab Host address (10.10.0.x) in three committed UTAS fixtures, tripping scripts/check-no-lab-addresses.sh. Replace with an RFC 5737 TEST-NET address (192.0.2.120) per the guard's own doctrine. Host header is plaintext metadata only (tests decode body_b64), so no test is affected. Pre-existing leak (fixtures committed at 0b66662/eb8311a); no lab address was introduced this session.