CodeRabbit CLI 0.5.0: Easier setup, clearer org selection, and a new health check

CodeRabbit CLI 0.5.0 introduces enhancements to streamline user experience by addressing common setup and usage challenges. The update focuses on simplifying authentication processes, improving the installation flow to include login, and providing clearer organization selection options for users managing multiple accounts. It introduces the `coderabbit doctor` command for easily diagnosing and resolving setup issues related to authentication, network access, git state, and configuration. This version also offers guidance for users on free plans when they encounter rate limits, suggesting an upgrade to Pro Plus to continue usage. Overall, the release aims to minimize setup confusion and provide better tools for maintaining an effective workflow with the CLI.