Module events 

Content-free domain events (ADR-007).

Enforcement: DomainEvent and EventEnvelope derive Copy. A String, Vec<u8>, or any heap-owning field is not Copy, so adding one would fail to compile. That makes “no prompt/response content on an event” a compile-time guarantee, not a code-review convention. Fixed-point integers (e.g. *_milli) stand in for ratios/scores so the type stays Copy + Eq.

Structs

EventEnvelope

Standard envelope (docs/ddd/domain-events.md): every event is correlated by SessionId and ordered by a logical step index.

Enums

DegradeReason

Why an optional pipeline stage was degraded (PRD risk policy made observable).

DomainEvent

Every fact the pipeline emits. Carries only ids, counts, enums, and fixed-point numbers — never content.