- Added bzip2 to the list of required tools for building.
- Provided a command snippet for installing the necessary packages, enhancing clarity for users setting up the environment.
- Added detailed instructions for two modes of operation in env.sh: normal mode and full toolchain mode.
- Updated the deactivation command to reflect changes in the toolchain registration process.
- Revised default CFLAGS for host/toolset builds to enhance clarity and consistency.
