Migrated from Method backlog

This issue was created from a legacy filesystem backlog card. GitHub Issues are now the live work tracker; repository docs remain Method evidence.

Source backlog: docs/method/backlog/v0.1.0/KERNEL_contract-aware-receipts-and-readings.md
Original lane: v0.1.0
Original legend: KERNEL

Original backlog card

Contract-Aware Receipts And Readings

Status: implemented local boundary.

Depends on:

• Accepted
  0016 - Wesley To Echo Toy Contract Proof
• Accepted
  0019 - Reading Envelope Family Boundary

Why now

Echo already content-addresses EINT intent bytes and already emits
ReadingEnvelope metadata for built-in observations. A generated contract path
is not enough unless any additional receipt and reading identity claims are
honest about what they actually commit to.

Echo should not return global-sounding state hashes for contract-local reads.
Contract observations should emit reading identities and envelopes whose scope
is explicit.

What it should look like

First inventory existing identity sources:

• EINT intent_id
• ingress id
• RegistryInfo
• generated op id
• payload bytes or payload hash
• ObservationArtifact::artifact_hash
• ReadingEnvelope

Only extend receipt and reading identity inputs where those existing identities
cannot honestly name the app contract artifact.

Candidate additional identity components:

• schema hash
• intent or observer kind
• basis or frontier
• payload hash
• generated handler or law version
• witness refs
• admission or residual posture

Acceptance criteria

• The same EINT bytes over the same basis produce the same receipt identity.
• Changing schema hash changes receipt identity.
• Changing payload changes receipt identity.
• Generated observation reading identity includes schema, observer or query op,
  basis, and aperture when those concepts are part of the generated read path.
• Unsupported or stale basis returns typed obstruction rather than a fake
  reading.
• Existing built-in observation tests remain green.

Non-goals

• Do not implement cryptographic proofs.
• Do not introduce IPA or commitment math.
• Do not require full Continuum export/import.
• Do not add consumer-specific receipt fields to Echo core.
• Do not duplicate intent_id or ReadingEnvelope if they already provide the
  honest identity needed for the first consumer.