Extract pure domain models

Extract pure domain logic from rapid prototype code

Salvaging high-value business logic from a vibe-coded prototype before architectural reengineering.

• · Rapid prototype codebase (Express, Sequelize, React, etc.)
• · DISCOVERY_REPORT.md identifying business rules and tech debt

• · domain/entities/, domain/values/, domain/rules/, domain/exceptions/ structure
• · Pure business models with Port abstractions for side effects
• · domain-purity-auditor certification report
• · Pure domain unit tests (zero mocks, zero database, instant)

• · domain-purity-auditor agent (scans for framework/IO leakages)
• · File system write for domain/ folder creation

• · Prototype codebase analyzed with explicit Preserve vs Replace classification
• · Business rules and calculations identified and isolated
• · Project structure allows domain/ folder creation

• · Framework dependency leaked into domain/: purity auditor flags, refactor to Port interface
• · Direct database client in domain/: violates purity, replace with IRepository port
• · Non-deterministic logic (timestamps, random): move to adapter layer

• · Explicit Preserve vs Replace classification prevents throwing away value
• · Port abstractions decouple business rules from infrastructure
• · domain-purity-auditor confirms zero framework/IO dependencies
• · Pure unit tests validate logic deterministically