feat(create): warn on --no-onboard for post-discovered-id agents (Issue #68)

.agents/skills/multi-agent-mux-create/scripts/create_session.sh

@@ -205,6 +205,10 @@ fi
 
 # Retrieve agent facts once
 eval "$("$(_delegate_py_bin)" -m lib_py.agents facts "$AGENT" 2>/dev/null || true)"
+# Issue #68: warn when --no-onboard is used with a post-discovered-id agent (adapter id_lifecycle via facts).
+if [ "$ONBOARD" = 0 ] && [ "${MAM_ID_POST_DISCOVERED:-0}" = 1 ]; then
+  echo "WARNING: --no-onboard: $AGENT records its conversation id only after its first turn; until then it is not in the registry, and another $AGENT session created in this folder waits for it (Issue #63, MAM_ID_ORDER_WAIT_S)." >&2
+fi
 
 CMD_FULL="$("$(_delegate_py_bin)" -m lib_py.agents spawn-spec "$AGENT" "$RESOLVED_BIN" "$SESSION_UUID" "${USE_WRAPPER:-0}" 2>/dev/null || true)"
 if [ -z "$CMD_FULL" ]; then