Various fixes & improvements
- fix: Make generated schema types an optional feature (96) by untitaker
- fix: Impl std::error::Error for SchemaError (95) by untitaker
- fix: Bump json-schema-diff to 0.1.2 (94) by untitaker
- docs: Clarify that bumping the version is part of the release process (92) by lynnagara
- feat: Remove unused fields from subscription results (88) by lynnagara
- ref: Loosen transaction schema (93) by lynnagara