fix(core): resolve bare $refs before dropping schema definitions

[LukasGold]

Closes #101

Problem

OSW.register_schema rewrote only the $refs reachable via the $..allOf jsonpath, then deleted schema["definitions"] unconditionally.

pydantic v1 wraps a nested-model $ref in allOf only when the field carries extra metadata, e.g. Field(description=...). A plain nested field:

class Outer(OswBaseModel):
    inner: Inner          # no Field(...) metadata

emits a bare {"$ref": "#/definitions/Inner"} on the property. Those refs were never rewritten, so deleting definitions left them dangling.

Changes

• Added a second pass over $..dollarref in register_schema that embeds the local #/definitions/... body in place, mirroring what the existing allOf loop does for wrapped refs.
• del schema["definitions"] now runs only when every local bare ref resolved, so an unresolvable ref keeps definitions rather than producing a dangling ref.
• The existing allOf loop is untouched; this is a strict superset of the previous behaviour.

Tests

tests/test_register_schema_nested_refs.py, two cases:

• bare $ref (no Field(...) metadata) is resolved like an allOf-wrapped one
• allOf-wrapped ref behaviour is unchanged

Verified the first test fails on unpatched code (AssertionError: assert not True from the dangling-ref check) and passes after the fix. Full unit suite: 170 passed, 1 skipped.

Note

Refs nested more than one level deep (a definition that itself holds a bare ref) are resolved in definitions but the already-embedded copy is not re-walked, since jsonpath.find collects matches before mutation. The pre-existing allOf loop has the same property, so this PR keeps the behaviour rather than widening scope. Worth a follow-up if such schemas occur in practice.

[github-actions]

Release preview

Merging this PR would release v2.2.2 (current: v2.2.1).

Changelog preview (truncated)

## v2.2.2 (2026-09-03)

### Bug Fixes

- **core**: Resolve bare $refs before dropping schema definitions
  ([`9c2ad6e`](https://github.com/OpenSemanticLab/osw-python/commit/9c2ad6e89c31e9b683c039b63eb6472429cbbd76))

_{Preview via python-semantic-release and conventional commits.}