v2.26.0

Changed

• Spine beat 2 (evidence/sources) now enforces the direction of evidence,
  across all 117 agents (team + genius) via the single generator
  scripts/generate-spine.py and its elaboration
  rules/agent-reference/zetetic-spine.md. The prior wording — "every claim traces
  to a source" — was direction-agnostic: it was satisfied equally by rigor (read a
  source, derive the code from it) and by fabrication (write the code, then find a
  resembling paper and attach the citation as post-hoc justification). Scientific
  rigor is source-first: start from a factual, verifiable, demonstrable source and
  produce the implementation from it. A citation attached after the fact to a
  lookalike paper is fabricated proof, not evidence — even when the citation is real,
  because the code was never derived from it.
• Beat 2 now names three refused failure modes, backed by observed provenance audits
  (invented arXiv ids, fabricated benchmark deltas, constants mislabeled with
  unrelated papers): retrofitted citation (added after the code, chosen for
  resemblance), resemblance ≠ prescription (a paper about your topic is not a
  source for your specific value/equation unless it states it and its experimental
  conditions match yours), and borrowed authority (a hardcoded constant wearing a
  paper's name with no line the paper actually prescribes). The honesty discriminator
  is the provenance comment written before the value plus an explicit
  "engineering-default / hand-tuned" disclaimer when a value is not paper-prescribed —
  never the citation alone.
• No source → "I don't know" and stop is now explicit that this is a gate failure,
  not a formatting gap to fill later: do not ship, then justify.

Notes

• Content-only change to the injected <zetetic-spine> blocks; no tool, hook, or
  memory-contract surface changed. scripts/generate-spine.py --check is clean
  (idempotent) and all seven release-gate memory suites pass locally.