buffa v0.3.0

buffa 0.2.0

Splits mod.rs generation into a separate protoc-gen-buffa-packaging
plugin and removes the mod_file= option from protoc-gen-buffa.

Breaking change for protoc-gen-buffa CLI users; library crates (buffa,
buffa-types, buffa-codegen, buffa-build) have no API breaks.

See CHANGELOG.md for the migration path.

buffa 0.1.0 — Rust Protocol Buffers with editions, views, and no_std

From-scratch protobuf runtime + codegen:

- Full schema support: proto2, proto3, editions 2023/2024 — with
  correct feature resolution (field_presence, enum_type, packed,
  utf8_validation) across syntax variants
- Binary wire format + proto3 canonical JSON (serde-based, feature-gated)
- Well-known types: Timestamp, Duration, Any, Struct/Value, FieldMask,
  wrappers — with ergonomic Rust conversions (chrono, serde_json)
- Zero-copy MessageView types borrowing the input buffer
- Open enums via EnumValue<E> preserving unknown values; closed enums
  route unknowns to UnknownFields
- Only requires no_std + alloc for runtime, views, and JSON
- Unknown field preservation on by default

Crates:
- buffa: runtime traits + encoding + views
- buffa-types: WKTs with chrono/serde_json integrations
- buffa-codegen: descriptor → TokenStream via quote/syn/prettyplease
- buffa-build: build.rs integration
- protoc-gen-buffa: protoc plugin + BSR plugin image

Passes the protobuf v33.5 conformance suite:
- 5539 (std) — 100% pass, excluding textproto (883 tests, not
  implemented)
- 5519 (no_std) — 20 Recommended-tier JSON tests need thread-local
  parse options
- 2797 (via-view) — binary decode only, verifies view/owned decoder
  parity

Runtime reflection not implemented.

See CHANGELOG.md, DESIGN.md, docs/guide.md.

License: Apache-2.0. Copyright 2026 Anthropic, PBC.
Vendored .proto sources (buffa-codegen/protos/, buffa-types/protos/)
are from protocolbuffers/protobuf v33.5 under BSD-3-Clause.