Function scoped_runtime 

pub fn scoped_runtime(
    shared: &RuntimeEnv,
    scoped_pool: Arc<ScopedMemoryPool>,
) -> Result<Arc<RuntimeEnv>, Error>

Builds a RuntimeEnv that reuses shared’s disk manager, caches and object-store registry but installs scoped_pool (already wrapping shared’s memory pool) as its memory pool. Takes the pool as a parameter, rather than constructing it internally, so callers can hand the (infallible) pool to QueryAuditState before this fallible step runs.