feat: add nix dependency and enhance socket permissions handling

apps/agent/docker/s6/cont-init.d/10-create-app-user

@@ -0,0 +1,58 @@
+#!/bin/sh
+set -eu
+
+YANPM_AGENT_UID="${YANPM_AGENT_UID:-1000}"
+YANPM_AGENT_GID="${YANPM_AGENT_GID:-1000}"
+# If a specific socket GID is requested, prefer that for the app group
+YANPM_AGENT_GID_EFFECTIVE="${YANPM_AGENT_SOCK_GID:-${YANPM_AGENT_GID}}"
+YANPM_AGENT_USER="${YANPM_AGENT_USER:-yanpm-agent}"
+YANPM_AGENT_GROUP="${YANPM_AGENT_GROUP:-yanpm-agent}"
+
+# Ensure group exists with desired GID
+if grep -qE "^${YANPM_AGENT_GROUP}:" /etc/group 2>/dev/null; then
+  existing_gid=$(awk -F: -v g="${YANPM_AGENT_GROUP}" '$1==g{print $3}' /etc/group)
+  if [ "${existing_gid}" != "${YANPM_AGENT_GID_EFFECTIVE}" ]; then
+    delgroup "${YANPM_AGENT_GROUP}" || true
+    addgroup -g "${YANPM_AGENT_GID_EFFECTIVE}" "${YANPM_AGENT_GROUP}"
+  fi
+else
+  addgroup -g "${YANPM_AGENT_GID_EFFECTIVE}" "${YANPM_AGENT_GROUP}"
+fi
+
+# Ensure user exists with desired UID and primary group
+if grep -qE "^${YANPM_AGENT_USER}:" /etc/passwd 2>/dev/null; then
+  existing_uid=$(awk -F: -v u="${YANPM_AGENT_USER}" '$1==u{print $3}' /etc/passwd)
+  if [ "${existing_uid}" != "${YANPM_AGENT_UID}" ]; then
+    deluser "${YANPM_AGENT_USER}" || true
+    adduser -D -u "${YANPM_AGENT_UID}" -G "${YANPM_AGENT_GROUP}" "${YANPM_AGENT_USER}"
+  fi
+else
+  adduser -D -u "${YANPM_AGENT_UID}" -G "${YANPM_AGENT_GROUP}" "${YANPM_AGENT_USER}"
+fi
+
+# Add app user to nginx group to allow reading configs
+addgroup "${YANPM_AGENT_USER}" nginx || true
+# Ensure runtime directories exist and fix ownership
+
+mkdir -p /var/run/yanpm /app
+if chown -R "${YANPM_AGENT_UID}:${YANPM_AGENT_GID_EFFECTIVE}" /var/run/yanpm 2>/dev/null; then
+  echo "chown: /var/run/yanpm -> ${YANPM_AGENT_UID}:${YANPM_AGENT_GID_EFFECTIVE}"
+else
+  echo "Warning: failed to chown /var/run/yanpm to ${YANPM_AGENT_UID}:${YANPM_AGENT_GID_EFFECTIVE}. This is common for bind-mounted host volumes or rootless Docker." >&2
+fi
+
+if chown -R "${YANPM_AGENT_UID}:${YANPM_AGENT_GID_EFFECTIVE}" /app/yanpm-agent 2>/dev/null; then
+  echo "chown: /app/yanpm-agent -> ${YANPM_AGENT_UID}:${YANPM_AGENT_GID_EFFECTIVE}"
+else
+  echo "Warning: failed to chown /app/yanpm-agent to ${YANPM_AGENT_UID}:${YANPM_AGENT_GID_EFFECTIVE}. Binary will still be used if permissions allow." >&2
+fi
+
+if chown "${YANPM_AGENT_UID}:${YANPM_AGENT_GID_EFFECTIVE}" /app 2>/dev/null; then
+  echo "chown: /app -> ${YANPM_AGENT_UID}:${YANPM_AGENT_GID_EFFECTIVE}"
+else
+  echo "Warning: failed to chown /app to ${YANPM_AGENT_UID}:${YANPM_AGENT_GID_EFFECTIVE}." >&2
+fi
+
+echo "App user and group setup complete. UID:${YANPM_AGENT_UID} GID:${YANPM_AGENT_GID_EFFECTIVE}"
+
+exit 0