Configurable acceptance for coordinated business deliverables #187

Problem observed in synthetic multi-agent acceptance

Execution completeness and business acceptance are separate. A five-work-item task can finish with complete model replies and a correct primary deliverable, yet the final report says a cohort passes a support-ticket rule per buyer using only order counts. A QA employee's caveat can be lost during synthesis.

The existing Reviewed task path and criterion checks should be reused where possible, not duplicated. Coordinated tasks need an explicit final-deliverable acceptance boundary.

Proposed scope (next product priority, not shipped)

• Opt-in, user-configured checks per task/template. Simple tasks keep the current minimal workflow.
• Bind checks to the selected deliverable(s), with immutable check/version/config snapshots.
• Typed facts/calculations with explicit numerator, denominator and units. Missing inputs produce an unknown/needs-review result, never a fabricated pass.
• Start with required fields and deterministic rate/threshold checks; do not hardcode financial rules into the core.
• Distinguish execution status from acceptance status in the API and Console. Preserve the original output and failed-check evidence.
• Gate downstream delivery/external actions where configured. No irreversible action on failed/unknown acceptance.
• Allow explicit human acceptance with audit. Keep model review advisory rather than a substitute for deterministic checks.

Acceptance evidence

1. Per-buyer threshold + order-only input => cannot pass; shows missing buyer count.
2. Complete correct inputs => deterministic acceptance with source evidence.
3. Conflicting prose such as unknown support compliance + all metrics passed => remains unaccepted pending correction/review.
4. No acceptance policy => simple task behavior unchanged.
5. Retry/replan/replay cannot alter pinned checks or silently accept another deliverable.

Separate follow-ups: measured tokens vs pricing estimates, and observable true worker parallelism. Production external-memory credential/deletion reconciliation remains tracked in #183.