Adopt shared receipt runtime sandbox fixture for DevSecOps Workroom handoff

[mdheller]

Parent: SocioProphet/prophet-platform#519

Scope

Adopt the shared receipt runtime sandbox fixture currently staged in Prophet Platform as a future external mirror.

Staged mirror in Prophet Platform:

• fixtures/external/agentplane/runtime-sandbox-run.shared-receipt.valid.json

Proposed AgentPlane destination:

• tests/fixtures/sandbox/runtime-sandbox-run.shared-receipt.valid.json

Purpose

This fixture gives AgentPlane, Sociosphere, and Prophet Workroom a single shared receipt identity for cross-plane handoff validation:

receipt://devsecops-workroom/shared-receipt/scope-d-example/001

Acceptance criteria

• Add the shared receipt runtime sandbox run fixture under AgentPlane sandbox fixtures.
• Ensure existing AgentPlane runtime sandbox run validator accepts the fixture or intentionally extend the validator if needed.
• Preserve non-claims:
  • no live infrastructure execution;
  • no Signadot feature parity certification;
  • teardown and leak-check gaps remain explicit.
• The fixture should preserve the existing runtime sandbox schema shape: runtimeRunId, requestRef, runtimeParityLevel, runStatus, environmentRef, dependencyGraphRef, routingRef, isolationRefs, evidenceRefs, receiptRefs, teardownState, leakCheckRef, and nonClaims.

Non-claims

This does not certify full runtime feature parity.

This does not imply a live sandbox has been allocated.

This does not transfer receipt authority to Prophet Platform.