Propagate API DTO into PutApiSpecificationInApim and use base DTO for OpenAPI updates

[ametelski]

Motivation

• Ensure the APIM put-specification path can reuse the already-available resource DTO instead of re-reading it from APIM when updating API specifications, enabling deterministic updates to the specification properties.

Description

• Change the PutApiSpecificationInApim delegate signature to accept a JsonObject baseDto parameter and update all resolver and caller sites accordingly.
• Update ResolvePutApiSpecificationInApim and its putOpenApiSpecification helper to operate on a cloned baseDto and merge the OpenAPI properties.format/properties.value into it instead of fetching the DTO again from APIM.
• Propagate the DTO through higher-level flows by changing calls to PutApiSpecificationInApim to pass the resource DTO (e.g. in putApi, putSpecification, putSpecification for workspace API, and integration/publisher tests).
• Adjust tests and test fixtures to match the new delegate signature and ensure callers provide dto where appropriate.

Testing

• Ran unit tests for the publisher project with dotnet test src/publisher.tests and all tests passed after updates to fixtures and callers.
• Ran integration tests with dotnet test src/integration.tests and the adjusted test that exercises API specification uploads passed.
• Verified compilation of the changed projects and that the updated delegate signature is satisfied across production and test code.

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Codex Task