Expand description
Storage-materialization subsystem: the actor that turns committed deltas into materialized columns in the columnar
store. Subscribes to CDC, batches writes per shape, drives the encoders in column/, and updates the catalog
registry so newly-written columns are visible to readers.
The subsystem owns the trade-off between materialization latency and write amplification - too aggressive and every commit pays a heavy column rewrite; too lazy and reads of recent data fall back to row-shaped storage. The actor’s policy is what decides when to flush and how to coalesce successive deltas into a single column rewrite.