Explain Cairo deref coercion with Deref/DerefMut traits and Target associated type; use when a request involves wrapper types, field access through wrappers, or deref behavior in Cairo.
SKILL.md
Cairo Deref Coercion
Overview
Guide how deref coercion works via Deref and DerefMut, and when it applies.
Quick Use
Read references/deref-coercion.md before answering.
Show the Deref trait and a wrapper example.
Note that DerefMut only applies to mutable variables.
Response Checklist
Implement Deref<T> with type Target and fn deref(self: T) -> Target.
Use deref coercion to access fields on the wrapped type.
Use DerefMut when you need mutable-only coercion; it does not make the target mutable by itself.