* test(portal-clis): isolate valid flag controls from live services
The LinkedIn and Freehire positive controls spawned live search CLIs and only checked for the absence of BAD_ARG, so attempted portal requests still left a green suite. Use loopback responses and assert successful output plus the constructed freshness, pagination and result-limit contract.
LinkedIn cards are verbatim excerpts from portapulito's actual captured response in PR #153; fixture provenance and original hashes are retained. Four Danish validation suites already stop at required-argument guards and need no change. This isolates these controls rather than claiming a whole-CI egress policy.
* docs(changelog): record fix for #581
