Add --version flag to audius-cli for version checking

[fuleinist]

Problem: Users have no way to check the audius-cli version from the command line, making debugging and CI/CD integration difficult.

Solution: Add a --version / -v flag to the audius-cli following standard CLI conventions (like docker --version, npm --version, etc.).

Use case: Operators can verify which version is installed before upgrading or reporting issues, and CI/CD pipelines can confirm the version as part of their workflow.