v0.17.0

candor 0.17 — the UX-audit engine round + spec floor bump. Query target validation (where/callers fail loud on a bad target, TIER-2 conformance), candor-ts node-fetch recall + prose-at-TTY output, empty-scope remedy text, and the /code-review fixes. Full four-way conformance: OK. See the spec §8 changelog + each CHANGELOG.