Captures current /data path (with bug history that forced single-batch
encoding), and four candidate redesigns: optimize the existing encoder,
DuckDB-WASM with Parquet, server-side DuckDB virtual server, and the
hybrid read-from-WASM/write-via-deltas variant. Each option weighed
against the forecasting write path, not just initial load. Intended as
a decision record so context survives a lost conversation.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
