Add support for aiokafka 0.13

[dolfinus]

Description

aiokafka 0.13 brings up wheels for Python 3.14. But it also introduces breaking change - api_version was removed from clients.

Added a conditional to pass api_version to aiokafka clients only if it was set explicitly by developer, which allows to use faststream with both 0.12.x and 0.13.x.
In case when developer passed api_version explicitly, it should be covered by aio-libs/aiokafka#1147 with proper deprecation policy.

Type of change

Please delete options that are not relevant.

• Documentation (typos, code examples, or any documentation updates)
• Bug fix (a non-breaking change that resolves an issue)
• New feature (a non-breaking change that adds functionality)
• Breaking change (a fix or feature that would disrupt existing functionality)
• This change requires a documentation update

Checklist

• My code adheres to the style guidelines of this project (just lint shows no errors)
• I have conducted a self-review of my own code
• I have made the necessary changes to the documentation
• My changes do not generate any new warnings
• I have added tests to validate the effectiveness of my fix or the functionality of my new feature
• Both new and existing unit tests pass successfully on my local environment by running just test-coverage
• I have ensured that static analysis tests are passing by running just static-analysis
• I have included code examples to illustrate the modifications