Spec design for do parity implementation

[aryeko]

Story

• do Parity-Capable App #73

Motivation

do variant must preserve contract while using its DI style.

Scope

In:

• Scenario mapping
• Shared-contract usage plan
• Verification order

Out:

• Publication formatting changes

Requirements

• Define parity-preserving handler design
• Define seed/state behavior

Acceptance criteria

• do design covers parity and run-single requirements

Verification

Commands:

• make -n parity-check

CI checks:

• (none)

Evidence:

• do design mapping

Artifacts

• Design consumed by T-034..T-036

Spec reference

• .sisyphus/plans/apps-implementation-roadmap.md
• Section: ST-010
• Quote: do Parity-Capable App

Dependencies

Blocked by:

• Document anti-drift usage guidance #78