feat: add portable NexusOS CLI and packaging

management/nexus-cli.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
-# ncp - Linux entry point. The CLI itself is management/ncp.py, which runs
+# ncp - Linux entry point. The CLI itself is management/cli.py, which runs
 # unchanged on Windows too (see management/ncp.cmd); this stays a shell script
 # because ~/.bashrc, launch_nexus.sh, bin/restore-linux.sh, controlpanel.py,
 # bin/panel/nexus-popup.py and management/nexus-app.sh all invoke this path.
@@ -8,9 +8,10 @@
 # directory drives itself instead of reaching into the real install.
 NEXUS_ROOT="$(cd "$(dirname "$(realpath "$0")")/.." && pwd)"
 
-# ncp.py needs psutil (venv), but its backup/restore path delegates to the
-# stdlib-only bin/sync.py and must work before the venv is built.
+# Prefer the project venv for the full desktop dependency set. The portable CLI
+# falls back to system Python when the package is installed without that venv.
 PY="$NEXUS_ROOT/Promethean/bin/python3"
 [ -x "$PY" ] || PY=python3
 
-exec "$PY" "$NEXUS_ROOT/management/ncp.py" "$@"
+cd "$NEXUS_ROOT"
+exec "$PY" -m management.cli "$@"