Conform confirm/* payload to published schema (subject/decision + DI proof)

[stormer78]

Summary

The wallet's confirm/* messages do not match the published confirm/request/0.1 / confirm/response/0.1 schemas. Conform them (requires coordinated changes on the RP side).

Current (non-conformant) behaviour

packages/core/src/inbound/confirm.ts:

• Request parsed as a flat DIDComm body { challenge, action, rpName? } (requires action).
• Response emitted as a flat DIDComm body { approved, challenge }.

Published spec (dtgwg-trust-tasks-tf/specs/confirm/{request,response}/0.1)

• A framework Trust-Task document (type + payload), not a flat DIDComm body.
• confirm/request payload: { subject, challenge, reason, ... }.
• confirm/response payload: { subject, challenge, decision: "approved"|"denied" } plus a Data Integrity proof — the proof is what the relying party verifies.

So today the wallet uses action/approved where the spec uses reason/decision, omits subject, packs fields flat instead of under payload, and attaches no proof (it relies on the authcrypt envelope for authentication).

Why this is cross-repo

confirm/* is peer-to-peer RP↔wallet. Conforming the wallet alone would break the live flow unless the RP counterpart (OpenVTC/rp-sdk-js and/or the demo RP) is updated to the spec shape at the same time. There is no confirm/0.2.

What to do

• Decide whether to adopt the spec shape (subject/decision/payload/DI-proof) or formally diverge.
• If adopting: update the wallet's parseConfirmRequest / buildConfirmResponse and the RP verifier together; add the DI proof.

Acceptance

• Wallet ↔ RP confirm round-trip uses the published confirm/{request,response}/0.1 document shape, or the divergence is documented as intentional.