Module trust_exchange 

Field-level pai-axiom trust exchange admission for Cortex (ADR 0042 / 0043).

This module consumes the typed envelopes from cortex_core::axiom_trust and runs the admission gate at the decomposed-field granularity. The existing crate::admission::AxiomMemoryAdmissionRequest still handles the generic ADR 0038 admission envelope; this module is the receiver-side field-level enforcement that the pai-axiom P6 acceptance request packet requires.

Hard structural refusals

• lifecycle != candidate_only → reject.
• same_loop_promotion_allowed == true → reject.
• durable_truth_promotion == eligible_after_independent_validation or full_execution_authority == eligible_after_independent_validation → reject (Cortex authority limit; ADR 0026 §4 hard wall).
• Expired or revoked token → reject.
• Missing required field-level contributor → reject.

Quarantine paths

• Quarantined or unknown quarantine state → quarantine with the named axiom.admission.quarantine.propagated invariant.
• Derived-from-quarantined per lineage → quarantine.
• Target-domain validation required and not Pass → quarantine.

Every AdmitCandidate decision carries an explicit forbidden_uses array — Cortex never lets AXIOM evidence imply durable truth.

Structs

AxiomTrustExchangeAdmissionRequest

Cortex-side admission request driven by the pai-axiom trust exchange envelopes (ADR 0042/0043).

Enums

AdmissionLifecycle

Required lifecycle assertion for a pai-axiom trust exchange admission.

ForbiddenUse

Authority-bearing uses forbidden on every AdmitCandidate path.

TrustExchangeAdmission

Final admission decision for a pai-axiom trust exchange admission.

Functions

forbidden_uses_for_candidate

Forbidden uses array attached to every AdmitCandidate / Quarantine decision. Cortex never grants AXIOM evidence durable authority.