30e8130394
Master's Zstandard physical encoding (#416) and this branch's packed chunk rows compose as orthogonal layers: packChunks shapes the logical storage records, compression shapes the physical bytes. The backend keeps both config keys; eventLines(events, packChunks) replaces master's singular eventLine helper and feeds encodeMaterialization/encodeEventBatch so packed rows flow through either encoding. Demo apps carry both passthroughs. The packed-row layout tests pin compression: 'none' (they assert textual line tags) and read through rawLogPath; zstd spec fixtures inline JSON.stringify for verbatim lines.