- Extract assert_hash_fields_consistent() helper that verifies presence
parity and value equality, replacing body.get()-based assertions that
treated missing keys and explicit nulls identically.
- Conftest seeded_asset fixture and seed-asset list assertions now check
key absence directly, so a regression that surfaces null fields would
be caught (validates exclude_none behavior).
- DRY duplicate hash expression in _build_asset_response.
- Add list-endpoint coverage asserting hash is present and consistent on
populated assets.
- Add schema-level test asserting AssetCreated inherits the hash field
from Asset, guarding against future inheritance drift.
Add a `hash` field to the Asset response schema that carries the same
value as the existing `asset_hash` field. Both fields are now populated
in _build_asset_response, so every Asset-returning endpoint (GET, POST,
PUT) includes both.
No existing fields are removed. Tests updated to assert both fields.
Co-authored-by: Matt Miller <MillerMedia@users.noreply.github.com>
