docs(taxonomy): AIF audit — third axis (cross-linguistic tradition) + labelling constraint (#498)

[jsboige]

Extends the AIF structural-audit record (docs/taxonomy/aif-structural-audit-method.md, merged #848) with a third axis of arbitrariness raised by jsboige in the 2026-07-22 conversation that the two-axis framing had missed.

What's added

• Axis C — the cross-linguistic tradition. Beyond uneven coverage (EN richest), traditions consecrated different visions across cultures, so the branches are not always aligned. The tree is a French-anchored projection of a family of partially-divergent language-specific trees, not a culture-neutral structure. Partly irreducible.
• §2.1 The internal-node labelling constraint (straddles A and C): internal nodes MUST bear a consecrated term with an external reference — no neologisms to balance the tree. Yields distorted labels (term stretched/narrowed) and grouping gated by lexical availability. Genuinely arbitrary, and language-dependent → surfaces axis C.
• §2.2 Evidential base is uneven and decaying — Wikipedia links stable; fallacy-dictionary links dying → archive.org. Audit should carry reference-reachability metadata.
• AIF as cross-linguistic solvent: the attack-mechanism is language-invariant, so the lens does not merely audit axis A — it can diagnose axis C (test two non-aligned consecrated labels for "same fallacy?" by mechanism).
• §4 decision rule → third layer (c) + a new bridge-node reading: high (a) heterogeneity / low (b) fail-loud / high (c) linguistic divergence = tradition divergence — annotate as a cross-cultural bridge, don't flatten. The tu quoque / whataboutisme specimen reframed as a joint axis-B and axis-C seam.
• §6: layer (c) needs two cheap chantier additions — reference-reachability metadata + a label-distortion flag on internal nodes.

Governance unchanged

Findings are FLAGS, never auto-reorganisations; gated on jsboige ratification; 0 prod-CSV write; pedagogical balance + labelling compromises remain legitimate. This is a conversation record, wording open to jsboige's revision.

Docs-only. Extends #498 / #847. Pointer in #458 TRACK 7.

🤖 Coordinator ai-01