Set registered schema subject correctly

[jekel]

What

Schema Registry server on new schema registration with specifiied subject could return no subject name in response,
like Confluent Schema Registry, so, register_schema_full_response method does not set it correctly, and returned registered schema is without subject.
This pull request fixs this issue.

[confluent-cla-assistant]

🎉 All Contributor License Agreements have been signed. Ready to merge.
✅ jekel
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[Copilot]

Pull Request Overview

This PR fixes an issue where the register_schema_full_response method doesn't correctly set the subject name on the registered schema when the Schema Registry server returns a response without a subject name (as allowed by the Confluent Schema Registry API).

• Adds logic to set the subject name on the registered schema if it's missing from the server response
• Ensures the returned registered schema object has the correct subject name populated

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/confluent_kafka/schema_registry/_sync/schema_registry_client.py	Adds subject name fallback logic in synchronous schema registry client
src/confluent_kafka/schema_registry/_async/schema_registry_client.py	Adds identical subject name fallback logic in asynchronous schema registry client

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[Copilot]

[nitpick] Direct mutation of the registered_schema object could lead to unexpected side effects. Consider creating a new RegisteredSchema instance with the correct subject or using a method that returns a properly initialized object.

Suggested change

	registered_schema.subject = subject_name
	registered_schema = RegisteredSchema(
	registered_schema.schema_id,
	registered_schema.schema,
	registered_schema.guid,
	subject_name,
	registered_schema.version
	)

[Copilot]

[nitpick] Direct mutation of the registered_schema object could lead to unexpected side effects. Consider creating a new RegisteredSchema instance with the correct subject or using a method that returns a properly initialized object.

Suggested change

	registered_schema.subject = subject_name
	registered_schema = RegisteredSchema(
	registered_schema.schema_id,
	registered_schema.schema,
	registered_schema.guid,
	subject_name,
	registered_schema.version
	)

[rayokota]

/sem-approve

[rayokota]

/sem-approve

[rayokota]

Thanks @jekel , LGTM