v0.4.0

Richer data objects, a typed exception hierarchy, and a fix for the audio pull

Breaking Changes

• JSON Output Shape → The CLI --json output now follows Pydantic's
  model_dump_json. Field names are unchanged and Japanese text stays verbatim,
  but the exact shape may differ from 0.3.0, which 0.x SemVer allows

• DTO Serialization → The Serializable mixin and its to_dict /
  to_json helpers are removed, serialize the Pydantic DTOs with
  model_dump / model_dump_json instead

• Bad-Argument Errors → The API now raises APIError from the new
  hierarchy on invalid arguments instead of ValueError

Added

• Data-Facing DTO Methods → The data objects gained pure helpers such as
  JMDictEntryDTO.all_pos / common_kanji, SenseDTO.all_tags /
  expand_tags, KanjiDTO.skip_codes / is_joyo, and LookupResult.has_*

• Exception Hierarchy → A new kotobase.exceptions module rooted at KotobaseError
  (DatabaseError, SourceExtractionError, DownloadError, APIError and
  their leaves), re-exported from the top-level package

• New API Methods → words_with_kanji, sentences_with_kanji and
  resolve_references (each accepting a DTO or a string), plus a match
  argument on by_radicals to find kanji containing any of a set of radicals
  as well as all of them

• DTO Arguments → The key-taking methods now accept a DTO as well as a
  string, reading the lookup key off the object, so a result from one call can
  be passed straight into another (e.g. sentences(entry), stroke_svg(kanji))

• Test Suite → A pytest suite run against a tiny fixture database, with
  coverage reported to Codecov across Python 3.10 to 3.13

Changed

• Pydantic DTOs → The data objects are now Pydantic models that carry
  data-facing behaviour and are built with model_validate straight from the
  ORM rows

• Typed Errors → Repositories wrap unexpected database failures as
  DatabaseError, and the build pipeline raises DownloadError /
  SourceExtractionError. The CLI renders any KotobaseError as a friendly
  message instead of a traceback

Fixed

• Audio Pull → kotobase db pull previously rebuilt the audio database
  locally from the Kanji Alive sources instead of pulling the pre-built
  kotobase-audio.db.zst release asset