Dereference OpenAPI schema returned by Function.openapi_schema

[aron]

This PR updates the openapi_schema method in Function and AsyncFunction to return a dereferenced API schema. This fixes a bug with transformation for models that output objects with named interfaces.

This PR also introduces a breaking change in that Function.openapi_schema() is now a method rather than a property to match AsyncFunction.openapi_schema() the latter needs to be a method because the lookup of the version is both lazy and async.

Lastly, the PR fixes an issue with the implementation where the latest OpenAPI schema was always returned. Now we return the version specified in the ref (or the latest if unspecified).

[Copilot]

Pull Request Overview

This PR ensures that Function.openapi_schema() and AsyncFunction.openapi_schema() return a fully dereferenced OpenAPI schema, honors version qualifiers in the model reference, and unifies the sync and async schema APIs.

• Introduces a _dereference_schema helper to inline $ref entries under components/schemas.
• Converts the sync openapi_schema from a property to a method (using a cached _openapi_schema) to match the async version.
• Fixes version lookup so that a specific version in the model ref is returned (or latest if unspecified).

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
tests/test_use.py	Added test_use_function_openapi_schema_dereferenced to verify inlined schemas and removal of unused definitions.
replicate/use.py	Added _dereference_schema, refactored/renamed openapi_schema logic for sync and async, and removed obsolete helpers.

Comments suppressed due to low confidence (3)

replicate/use.py:62

• The removal of _download_file likely breaks _process_output_with_schema, which still references it for file downloads. Restoring this helper or refactoring the download logic would prevent a NameError when handling file-based outputs.

def _download_file(url: str) -> Path:

replicate/use.py:450

• There’s no test covering the new behavior when a version is explicitly specified in the ref string. Adding a test that uses replicate.use("owner/model@v1.2.3") and asserts the correct schema is fetched would ensure this path stays validated.

_, _, model_version = self._parsed_ref

replicate/use.py:669

• [nitpick] The error message here differs from the sync variant (has no latest version). Consider unifying these messages for consistency (e.g. always has no latest version).

msg = f"Model {model.owner}/{model.name} has no version"