feat(workspaces): implement workspace container image and initial hub api

packages/workspace-manager/docker/entrypoint.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+# Copyright 2026 Google LLC
+# SPDX-License-Identifier: Apache-2.0
+
+# Ensure GH_TOKEN is set from memory-only mount if available
+if [ -f /dev/shm/.gh_token ]; then
+    export GH_TOKEN=$(cat /dev/shm/.gh_token)
+    echo "GitHub token injected from memory."
+fi
+
+# Start shpool daemon in the background
+/usr/local/bin/shpool daemon &
+
+# Restore ~/.gemini settings if they are provided in a mount or PD
+# (Assuming PD is mounted at /home/node/persistent_home for now)
+if [ -d /home/node/persistent_home/.gemini ]; then
+    rsync -a /home/node/persistent_home/.gemini/ /home/node/.gemini/
+fi
+
+# Execute the CMD passed to docker
+exec "$@"