- Added user mapping (UID:GID) to Docker Compose services to prevent root-owned files
- Export current user's UID/GID in build.sh for Docker Compose
- Enhanced clean build to handle permission issues gracefully:
* Try normal cleanup first
* Fallback to container-based cleanup for root-owned files
* Ultimate fallback to sudo if needed
- Added cleanup for all Docker volumes (build, source, kernel, target caches)
Fixes 'Permission denied' errors when cleaning output files created by Docker containers.
