improve: always add marimo in sandbox

Necessary so sandboxed notebooks can be run as scripts with uv run nb.py.

marimo/_runtime/runtime.py

@@ -549,6 +549,12 @@ def _update_runtime_from_user_config(self, config: MarimoConfig) -> None:
         ):
             self.package_manager = create_package_manager(package_manager)
 
+        if self._should_update_script_metadata():
+            # All marimo notebooks depend on the marimo package; if the
+            # notebook already has an optional dependency group with marimo,
+            # such as marimo[sql], this is a NOOP.
+            self._update_script_metadata(["marimo"])
+
         if (
             autoreload_mode == "lazy" or autoreload_mode == "autorun"
             # Pyodide doesn't support hot module reloading