PropertyDamage.ProjectionError exception (PropertyDamage v0.2.0)

Raised internally when a projection's apply/2 raises while folding a command or event into state.

A raising apply/2 is a legitimate way for a projection to signal a transition invariant violation (see PropertyDamage.Model.Projection). The executor catches this and turns it into a reported failure ({:projection_violation, projection, exception}) rather than letting it crash the whole run.