fix: create /run/sshd, fix websockets API deprecation, root password

- mkdir -p /run/sshd in Dockerfile and start-server.sh (sshd needs it)
- Use websockets.asyncio.server.serve with fallback for compatibility
- Set root password for SSH login as root

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Dockerfile

@@ -32,12 +32,14 @@ RUN curl -fsSL https://claude.ai/install.sh | bash \
 # Snapshot base package list (to detect user-added packages later)
 RUN dpkg-query -W -f='${Package}\n' | sort > /etc/base-packages.list
 
-# SSH host keys (system-wide, for root sshd)
-RUN ssh-keygen -A
+# SSH: host keys + privilege separation directory
+RUN ssh-keygen -A && mkdir -p /run/sshd
 
 # User account (for SSH login); container runs as root for system persistence
 RUN useradd -m -u 1000 -s /bin/bash -p "$(openssl passwd -6 huggingrun)" user 2>/dev/null || true
-RUN mkdir -p /data && chown 1000:1000 /data
+# Root password for SSH login as root
+RUN echo "root:huggingrun" | chpasswd 2>/dev/null || usermod -p "$(openssl passwd -6 huggingrun)" root
+RUN mkdir -p /data
 
 # nginx + bridge + startup scripts
 COPY ubuntu-server/nginx.conf /etc/nginx/nginx.conf

ubuntu-server/start-server.sh

@@ -92,6 +92,7 @@ echo "[start-server] Persistence background PID=$PERSIST_PID" >&2
 trap 'echo "[start-server] Saving system before exit..." >&2; save_system; exit 0' SIGTERM SIGINT
 
 # ── Phase 3: Start sshd ─────────────────────────────────────────────
+mkdir -p /run/sshd
 echo "[start-server] Starting sshd on 127.0.0.1:$SSH_PORT ..." >&2
 /usr/sbin/sshd -o "Port=$SSH_PORT" \
     -o "ListenAddress=127.0.0.1" \

ubuntu-server/ws-ssh-bridge.py

@@ -13,12 +13,16 @@ import sys
 
 try:
     import websockets
-    from websockets.server import serve
 except ImportError:
     print("[ws-ssh-bridge] websockets not installed, pip installing...", file=sys.stderr)
     import subprocess
     subprocess.check_call([sys.executable, "-m", "pip", "install", "websockets", "-q"])
     import websockets
+
+# Support both old and new websockets API
+try:
+    from websockets.asyncio.server import serve
+except ImportError:
     from websockets.server import serve
 
 SSH_HOST = "127.0.0.1"