docs(specs): group 2 feedback as amendments, and lift out what was never specified

Following the Kiro workflow rather than continuing to write tasks.

**A workflow error, corrected.** Two task groups -- a counter-example
ledger, and per-repository evolutionary prompting so developers can commit
dismissals and evolve the harness -- were appended to contributor-scan's
tasks.md on 2026-09-09 without passing requirements or design. They are not
refinements of scan integration; they are a different feature, and writing
them as tasks skipped the two phases that decide whether a feature is
shaped right. They are lifted to .kiro/specs/finding-feedback-loop/, at
brief, unapproved.

That brief states the boundary the design turns on: an optimiser may evolve
the QUESTION (the judge and residual prompts, which are how we ask) and
never the FACTS (tables, rulesets, the declared policy file, which are what
we claim). The closed-loop leak measured on 2026-09-05 is why -- five of
eleven candidate shapes were taught by the holdout pairs they then
recovered, reporting a -0.059 holdout Youden as +0.059. It also states the
acceptance test for the model's role: revert the three matcher fixes and
see whether the grouping rediscovers the known causes.

**Three requirements amendments, drafted and unapproved**, at the end of
contributor-scan/requirements.md:

- Req 5 should state what a report may repeat. libpng emitted 198 findings
  and nothing in the spec forbade it. Task 2.11 fixed pattern noise; the
  model layer's own suspicion band is still 38 of vampi's 60, and it is the
  same epistemic class -- an enumerated candidate the graph could not
  decide and an LLM affirmed.
- A family that cannot decide a class must say so. c/memory scored zero
  true positives on 89k lines of C for a structural reason, and a silent
  scan reads as a clean bill of health. Worse than noise because it is
  quiet, and the one failure mode the rung ladder does not already guard.
- Req 4.1 is satisfied by a checkout that cannot demonstrate detection at
  all -- libpng's CVE is out of family and no version of it can be
  otherwise. It should require one that can.

And what group 2 confirmed rather than changed: Req 8's overfitting warning
stopped a rule being extended until one repository was clean and forced the
access-control work onto pairs nobody tuned against; Req 3.3's honesty
counters are what made a budget stopping free work visible at all; and Req
11.2's byte-identical gates held through all nine defect fixes, which says
from the other side that the corpus could not have caught any of them.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01T7XD7x5KonMdmGRkp63EQG

.kiro/specs/contributor-scan/spec.json

@@ -1,7 +1,7 @@
 {
   "feature_name": "contributor-scan",
   "created_at": "2026-09-08T20:00:00Z",
-  "updated_at": "2026-09-09T09:30:00Z",
+  "updated_at": "2026-09-09T12:00:00Z",
   "language": "en",
   "phase": "implementation",
   "approvals": {
@@ -22,5 +22,5 @@
   "depends_on": [
     "model-grounded-detection"
   ],
-  "approval_note": "2026-09-08 brief drafted after the maintainer asked what the spec state was and whether anything was forgotten. It was: model-grounded-detection is 16/16 complete and its arbiter is measured at 86.7% pair-correct / 6.7% leak, but the model layer has ZERO production callers -- ousast scan does not use it, so the feature is complete and unshipped at once. That is a scope gap in the predecessor (it had no task saying 'make this reachable', and its byte-identical-gates requirement is satisfied precisely because nothing is wired). This spec covers scan integration, whole-repo scanning against known vulnerable repositories, the deferred memory-family decision, and records the pipeline, ops and corpus work delivered outside any spec. Not approved; requirements not generated. ; 2026-09-08 requirements generated at the maintainer's direction ('we follow the spec and build integration afterwards'). ; 2026-09-09 requirements approved and design generated ('let us continue with these'): the model layer joins as one stage inside MAP beside the obligations checker, one CPG per scan, regions from entry points, a total budget rather than a per-region cap. Phase 2 (the first run on a pinned real repository) can invalidate the rest and comes before shipping. ; 2026-09-09 tasks approved by the maintainer ('approve the tasks and start group 1'); implementing group 1 (regions, driver, MAP stage)."
+  "approval_note": "2026-09-08 brief drafted after the maintainer asked what the spec state was and whether anything was forgotten. It was: model-grounded-detection is 16/16 complete and its arbiter is measured at 86.7% pair-correct / 6.7% leak, but the model layer has ZERO production callers -- ousast scan does not use it, so the feature is complete and unshipped at once. That is a scope gap in the predecessor (it had no task saying 'make this reachable', and its byte-identical-gates requirement is satisfied precisely because nothing is wired). This spec covers scan integration, whole-repo scanning against known vulnerable repositories, the deferred memory-family decision, and records the pipeline, ops and corpus work delivered outside any spec. Not approved; requirements not generated. ; 2026-09-08 requirements generated at the maintainer's direction ('we follow the spec and build integration afterwards'). ; 2026-09-09 requirements approved and design generated ('let us continue with these'): the model layer joins as one stage inside MAP beside the obligations checker, one CPG per scan, regions from entry points, a total budget rather than a per-region cap. Phase 2 (the first run on a pinned real repository) can invalidate the rest and comes before shipping. ; 2026-09-09 tasks approved by the maintainer ('approve the tasks and start group 1'); implementing group 1 (regions, driver, MAP stage). ; 2026-09-09 group 2 complete except 2.8/2.9/2.13-2.16, and it reshaped the phase as intended. Nine engine defects found by measurement and none by review, gates byte-identical through every fix -- which says the pair corpus could not have caught any of them. Three requirements amendments are DRAFTED AND UNAPPROVED at the end of requirements.md: (A) Req 5 should state what a report may repeat, because libpng emitted 198 findings with nothing in the spec forbidding it, and the model layer's own suspicion band is still 38 of vampi's 60; (B) a family that cannot decide a class must say so, because c/memory scored zero true positives on 89k lines of C for a structural reason and a silent scan reads as a clean bill of health; (C) Req 4.1 is satisfied by a checkout that cannot demonstrate detection at all, so it should require one that can. Separately, two task groups appended to tasks.md without passing requirements or design have been LIFTED OUT to the new finding-feedback-loop spec, where they belong."
 }