Update init.sh

[ewassef]

This pull request enhances the init.sh script with improved Docker permissions handling, better OS and architecture detection, and streamlined release asset downloading. It also removes unused or outdated code for clarity and maintainability.

Docker permissions and OS-specific setup:

• Enhanced Docker permissions handling for Linux and macOS, including checks for Docker group membership, Docker CLI installation, and Docker Desktop status. Added support for OS detection and error handling for unsupported systems.

OS and architecture detection:

• Added logic to detect the operating system and architecture (linux, darwin, x64, arm64) and dynamically set the appropriate release asset name.

Release asset downloading:

• Simplified release asset downloading by removing the need for a GitHub token and using the browser_download_url field instead of asset ID. Improved error messaging for missing assets.

Path management:

• Restored logic to update the user's PATH with the binary directory if not already present, ensuring the CLI is accessible after installation.

Code cleanup:

• Removed outdated or commented-out code, such as unused sudo gpasswd commands and redundant token-based asset download logic, for improved readability and maintainability.