chore(zarr-metadata): build 0.5.0 changelog (#4266)

* chore(zarr-metadata): note the sdist allowlist, and let misc entries speak

#4248 gave this package's sdist an explicit allowlist and merged without a
news fragment, so a user-visible packaging change was about to miss the
0.5.0 notes. Add one.

Filing it as `misc` exposed that towncrier's built-in `misc` type sets
`showcontent = false`: the entry would render as a bare PR link, which tells
a reader nothing. Restate all five types the `changes/README.md` menu offers
— declaring any type replaces the built-in set — as the defaults verbatim
except for `misc`, which now shows its content. A change worth a release
note is worth a sentence, whatever its category.

Assisted-by: ClaudeCode:claude-opus-5

* chore(zarr-metadata): build 0.5.0 changelog

Consume the pending news fragments — #4232's constant-naming-grammar removal
note, #4264's note widening `JSONValue`'s array arm to the covariant
`Sequence`, and #4248's sdist allowlist — into CHANGELOG.md via towncrier
for the zarr_metadata-v0.5.0 release.

Minor, not patch: the `JSONValue` widening changes a published type's
meaning for every consumer that annotates against it, and #4232 removes the
old version-last constant spellings outright.

Assisted-by: ClaudeCode:claude-opus-5

Author: d-v-b

packages/zarr-metadata/CHANGELOG.md

@@ -2,6 +2,96 @@
 
 <!-- towncrier release notes start -->
 
+## 0.5.0 (2026-08-14)
+
+### Bugfixes
+
+- `JSONValue`'s array arm is now the covariant `Sequence["JSONValue"]` rather
+  than the invariant `list["JSONValue"] | tuple["JSONValue", ...]`. Values typed
+  with a narrower element type — a `list[str]` field on a TypedDict, a
+  `Sequence[float]` — now count as JSON values, and TypedDicts whose fields
+  carry precise types are now assignable to `Mapping[str, JSONValue]`.
+  Type-level cost, accepted deliberately: `Sequence` says nothing about the
+  concrete container and admits `str`/`bytes`, so runtime code narrowing a JSON
+  array must exclude `str`/`bytes`/`bytearray` — as it already had to, since
+  `str` was always a union arm. ([#4264](https://github.com/zarr-developers/zarr-python/pull/4264))
+
+### Deprecations and Removals
+
+- Unified the naming grammar for SCREAMING_SNAKE constants with the one used for
+  type names. A constant's name is now a purely syntactic transformation of the
+  name of the `Literal` type it manifests, so the format version is spelled
+  `ZARR_V2`/`ZARR_V3` and comes first, matching the `ZarrV2`/`ZarrV3` prefix on
+  the corresponding type:
+
+  - `ARRAY_METADATA_STORE_KEY_V2` → `ZARR_V2_ARRAY_METADATA_STORE_KEY`
+  - `ARRAY_METADATA_STORE_KEY_V3` → `ZARR_V3_ARRAY_METADATA_STORE_KEY`
+  - `ATTRIBUTES_STORE_KEY_V2` → `ZARR_V2_ATTRIBUTES_STORE_KEY`
+  - `GROUP_METADATA_STORE_KEY_V2` → `ZARR_V2_GROUP_METADATA_STORE_KEY`
+  - `GROUP_METADATA_STORE_KEY_V3` → `ZARR_V3_GROUP_METADATA_STORE_KEY`
+  - `CONSOLIDATED_METADATA_STORE_KEY_V2` → `ZARR_V2_CONSOLIDATED_METADATA_STORE_KEY`
+  - `ARRAY_ORDER_V2` → `ZARR_V2_ARRAY_ORDER`
+  - `ARRAY_DIMENSION_SEPARATOR_V2` → `ZARR_V2_ARRAY_DIMENSION_SEPARATOR`
+  - `CONSOLIDATED_METADATA_KEY_V3` → `ZARR_V3_CONSOLIDATED_METADATA_KEY`
+
+  The old names are removed, not aliased. This supersedes the 0.4.0 convention
+  under which type names put the format version first while constants put it
+  last: every constant that manifests a `Literal` type now follows the same rule
+  as that type.
+
+  The last of those is the one rename the syntactic rule does not force:
+  `ZARR_V3_CONSOLIDATED_METADATA_KEY` manifests no `Literal` type, so it is
+  outside the rule and was renamed for consistency with its siblings.
+
+  Digit runs stay glued to the token they follow, so spec vocabulary is
+  preserved: `Uint8DataTypeName` pairs with `UINT8_DATA_TYPE_NAME` (not
+  `UINT_8_...`) and `Crc32cCodecName` with `CRC32C_CODEC_NAME`. No dtype, codec,
+  chunk-grid, or chunk-key-encoding constant changed name.
+
+  Constants that do not manifest a `Literal` type are outside the rule and are
+  unchanged: the `*_METADATA_*_KEYS_V2`/`_V3` key sets, the
+  `CANONICAL_*_HEX_FLOAT*` bit patterns, and `UNSET`. The key sets keep the
+  version-last spelling, so `zarr_metadata.model` exports both
+  `ARRAY_METADATA_REQUIRED_KEYS_V2` and `ZARR_V2_ARRAY_METADATA_STORE_KEY`. They
+  name validation policy rather than a spec document, have no paired type to
+  derive from, and renaming them would be a second breaking change buying only
+  cosmetic consistency — so it is deliberately deferred.
+
+  `tests/test_public_api.py::test_constant_names_derive_from_their_type_names`
+  derives every constant name from the type it manifests and asserts they match,
+  so the two grammars cannot diverge again.
+
+  Store keys also moved to the modules that describe the documents they name,
+  matching the package's layering (the `v2`/`v3` modules describe the specs; the
+  `model` layer is built on top of them). `ZARR_V2_ATTRIBUTES_STORE_KEY` now
+  lives in `zarr_metadata.v2.attributes` beside the `.zattrs` type it names,
+  rather than in the array model; the other five moved likewise, and
+  `ZarrV2AttributesStoreKey` is no longer an array-specific concept.
+  `zarr_metadata.model` re-exports all six, so
+  `from zarr_metadata.model import ZARR_V2_ARRAY_METADATA_STORE_KEY` is
+  unaffected.
+
+  `CONSOLIDATED_METADATA_KEY_V3` moved to `zarr_metadata.v3.consolidated` and was
+  renamed to `ZARR_V3_CONSOLIDATED_METADATA_KEY` for consistency. It is not a
+  store key: unlike v2's `.zmetadata` file, v3 consolidated metadata is embedded
+  as an extension field inside the group's own `zarr.json`.
+
+  All seven keys and the six store-key `Literal` aliases are now also exported
+  from the top-level `zarr_metadata` namespace, alongside the document types and
+  the rest of the spec vocabulary, so `from zarr_metadata import
+  ZARR_V2_ARRAY_METADATA_STORE_KEY` works. The model layer's validators, parsers,
+  type guards, and metadata key sets remain `zarr_metadata.model` imports.
+
+  ([#4232](https://github.com/zarr-developers/zarr-python/pull/4232))
+
+### Misc
+
+- The source distribution now ships an explicit allowlist (`/src`, `/tests`,
+  `/docs`, `/mkdocs.yml`, `/justfile`, `/CHANGELOG.md`) rather than whatever
+  happens to sit in the package directory, so an sdist both tests and documents
+  itself and cannot pick up scratch files from the tree it was built in. ([#4248](https://github.com/zarr-developers/zarr-python/pull/4248))
+
+
 ## 0.4.0 (2026-07-29)
 
 ### Features

packages/zarr-metadata/changes/4232.removal.md

@@ -137,3 +137,33 @@ underlines = ["", "", ""]
 title_format = "## {version} ({project_date})"
 issue_format = "[#{issue}](https://github.com/zarr-developers/zarr-python/pull/{issue})"
 start_string = "<!-- towncrier release notes start -->\n"
+
+# Declaring any type replaces towncrier's built-in set, so all five the
+# `changes/README.md` menu offers are restated here. They are the defaults
+# verbatim except for `misc`, whose `showcontent` towncrier defaults to false:
+# a `misc` entry would render as a bare PR link, which tells a reader nothing.
+# A change worth a release note is worth a sentence, whatever its category.
+[[tool.towncrier.type]]
+directory = "feature"
+name = "Features"
+showcontent = true
+
+[[tool.towncrier.type]]
+directory = "bugfix"
+name = "Bugfixes"
+showcontent = true
+
+[[tool.towncrier.type]]
+directory = "doc"
+name = "Improved Documentation"
+showcontent = true
+
+[[tool.towncrier.type]]
+directory = "removal"
+name = "Deprecations and Removals"
+showcontent = true
+
+[[tool.towncrier.type]]
+directory = "misc"
+name = "Misc"
+showcontent = true