Function render_no_shuffle_ensembles 

async fn render_no_shuffle_ensembles<C>(
    txn: &C,
    actor_id_counter: &AtomicU32,
    ensembles: &[NoShuffleEnsemble],
    fragment_map: &HashMap<FragmentId, Model>,
    job_map: &HashMap<JobId, Model>,
    worker_map: &BTreeMap<WorkerId, WorkerInfo>,
    adaptive_parallelism_strategy: AdaptiveParallelismStrategy,
) -> MetaResult<FragmentRenderMap>
where
    C: ConnectionTrait,

Core rendering routine that consumes no-shuffle ensembles and produces InflightFragmentInfos by:

• determining the eligible worker pools and effective parallelism,
• generating actor→worker assignments plus vnode bitmaps and source splits,
• grouping the rendered fragments by database and streaming job.