v0.6.2

Fixed

• FieldValue's recursive mapping arm uses Mapping[str, FieldValue] (covariant in its value type) instead of the invariant dict[str, FieldValue]. dict is invariant in V, so any concrete dict[str, X] (where X is a structural subset of FieldValue) was rejected by type checkers at every Model.with_(field=value) call site, forcing callers to insert cast("dict[str, FieldValue]", ...) boilerplate. The runtime contract is unchanged: every dict is also a Mapping, and the encoder pipeline's isinstance(v, dict) checks keep matching real dict payloads. (#36)

Full changelog: https://github.com/panproto/didactic/blob/main/CHANGELOG.md