T03: point review at the harness, and state what review cannot catch

The review step targeted the survey. Every serious error in this project
has been in measurement or build configuration, so the loop was
adversarially reviewing the artifact cheapest to fix and leaving
unreviewed the one where errors occur.

Step 2 now routes by risk: when the claim rests on numbers, the reviewer
gets the harness and the evidence file too, and must reproduce the
number independently rather than read about it.

The addition that matters more, because it was learned the hard way: a
reviewer re-derives the author's claims and therefore inherits the
author's SAMPLING. CB-WP-0002's dedup invariant was checked twice --
survey 206/206 groups, then the reviewer independently -- and both used
the main transcript. It is false in the 8-response subagent tree neither
looked at. Two independent verifications, one shared blind spot.

  Rule: the reviewer re-derives on a different sample than the author
  used, and where only one sample exists, says so rather than reporting
  a clean verify.

Also recorded: what review demonstrably DOES do. $0.66 and $1.11 across
two passes, ~1% of each, both finding approval-blocking defects. Cost is
not a reason to skip it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

workplans/CB-WP-0003-loop-hardening.md

@@ -124,7 +124,7 @@ dedup.
 
 ```task
 id: CB-WP-0003-T03
-status: todo
+status: done
 priority: medium
 state_hub_task_id: "1365b35d-4539-489a-beff-c072221e4702"
 ```