feat(delphi): Q10 carve-out — pin large-conv cutoffs to certify the deterministic full-PCA path

[jucor]

Clojure's conv-update switches to mini-batch partial-pca on an UNSEEDED
Mersenne-Twister row sample when n-ptpts > 10000 or n-cmts > 5000
(conversation.clj:757-815) — no deterministic reference exists on that
path, even between two Clojure runs (CLOJURE_QUIRKS.md Q10; root cause of
the pakistan/engage/bg2050 mid-chain battery divergences, verified to
switch at exactly the first divergent step on all three).

The replay driver now passes {:ptpt-cutoff :cmt-cutoff} = 10^9 into
conv-update so certification exercises the full-PCA path at every size
(math/dev/ change only — no math sources touched), and certify.py's
acceptance notice logs the carve-out on every run, like Q7's.
Python keeps full PCA at all sizes (no change needed).

commit-id:7c20f8e1

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Stack:

• docs(delphi): overnight pre-cutover audit (s6) — CUTOVER_RUNBOOK + journal #2659
• feat(delphi): zid-sharding for the math poller — one shard = one process #2658
• ci: run postgres integration tests #2637
• feat(delphi): poller-equivalence harness (goal condition 2) — PASSES live on vw + pc-meta-02 #2657
• feat(math): moderation + restart replay parity — mod_update, restart-seam restore, Q13-Q18 #2656
• docs(delphi): R1-parity goal docs, journal (2026-07-18 → 07-24 s5), quirks + divergence ledger #2626
• feat(delphi): Q12 carve-out — pin the cold-tick PCA start to ones in both replay drivers #2655
• feat(math): Q11 — replicate vectorz distance cancellation in legacy kmeans #2654
• feat(math): small-N degenerate parity — run the real math on tiny matrices in clojure-legacy mode #2653
• feat(delphi): Q10 carve-out — pin large-conv cutoffs to certify the deterministic full-PCA path #2652 ⬅
• feat(delphi): replay loader resolves private datasets under real_data/.local #2651
• feat(math): Clojure hash-map iteration order for the in-conv greedy tie-break (legacy) #2650
• feat(math): clojure-legacy blob emission + selection parity — Clojure-exact math_main at step 0 #2649
• feat(delphi): acceptance canonicalization — suppress cross-engine ordering artifacts in certify comparer #2648
• feat(delphi): certify.py battery runner + focuser + fingerprint ledger (Spec A, Phase 0) #2647
• feat(delphi): prodclone extractor — feature-filtered dataset export (Spec B) #2646
• feat(math): un-mirror priority_metric (#2571 resolved) + Q2 prev-tick group-votes #2645
• feat(math): participant-ban leak replication in clojure-legacy mode (Q1) #2644
• feat(delphi): Clojure timing probe (Spec C) #2643
• feat(math): degenerate-tick group-clusterings overwrite + <2-participants edge (legacy mode) #2642
• refactor(math): move impl-flag resolver to polismath/utils/env_flags.py #2641
• feat(delphi): Python math poller service (phase 1) — Clojure math-container replacement #2625
• fix(delphi): Clojure-parity math writers + committing write path in PostgresClient #2624
• feat(math): in-conv greedy floor + persistent carry (PR-E) #2623
• feat(math): Clojure-exact base-cluster lineage + warm start (PR-C) #2622
• feat(math): replay harness H-B — Clojure Mode A driver (dev/replay.clj) + cross-language comparer shim #2621
• feat(math): group-k-smoother in clojure-legacy engine mode (PR-D smoother) #2620
• feat(math): PCA warm start in clojure-legacy engine mode (PR-B) #2640
• feat(math): add POLISMATH_ENGINE_MODE flag + prev-tick warm-start scaffolding (PR-A) #2618
• feat(delphi): replay harness H-A — schedule spec+slicer, Python driver, store, step comparer, CLI #2639
• fix(delphi): cold-start generator copies FULL revote history (no DISTINCT ON dedup) #2638
• fix(math): correct comment-extremity sign in pca_project_cmnts (D1b) #2615
• docs(delphi): add math-algorithm history & routing-regression reference #2613

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⚠️ Part of a stack created by spr. Do not merge manually using the UI - doing so may have unexpected results.

[Copilot]

Pull request overview

This PR makes the Clojure replay/certification reference deterministic for very large conversations by forcing conv-update to stay on the full-PCA (“small-conv”) path regardless of participant/comment counts, avoiding the unseeded mini-batch PCA sampling path (CLOJURE_QUIRKS Q10). It also updates the certification acceptance notice so every run explicitly documents that this carve-out is in effect.

Changes:

• Pin :ptpt-cutoff / :cmt-cutoff to 10^9 in the Clojure Mode A replay driver and pass these options into conv/conv-update on every step.
• Emit a per-run stderr log line in the Clojure driver indicating the Q10 carve-out is active.
• Expand certify.py’s ACCEPTANCE_NOTICE to include the Q10 carve-out statement alongside the existing Q7 notice.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
math/dev/replay.clj	Forces deterministic full-PCA path during Clojure replay by passing very large cutoffs into conv-update, and logs the Q10 carve-out.
delphi/polismath/replay/certify.py	Updates the always-printed acceptance notice to document the Q10 carve-out during certification runs.

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