- lib/common.sh: add require_local_os, require_remote_os, require_remote_pkg_manager
- setup/macbook.sh: require macOS (Darwin)
- setup/unraid.sh: require remote is Linux
- setup/fedora.sh: require remote is Linux + has dnf (RPM-based)
- manage_runner.sh: native runner add/remove requires macOS
- run_all.sh: control plane must be macOS
- preflight.sh: 3 new checks (1: local=macOS, 2: Unraid=Linux, 3: Fedora=Linux+dnf)
- phase5_migrate_pipelines.sh: fix sed -i to be portable (no macOS-only syntax)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>