Constant WHOLE_FILE_REFUSE_BYTES 

const WHOLE_FILE_REFUSE_BYTES: i64 = _; // 67_108_864i64

A non-circular output this large is never read whole: loading it holds the store’s connection mutex for the whole read (about 15 s for a 1.3 GB transcript), stalling every agent’s appends and every pane’s reads in this process (docs/reports/REPORT_AGENT_OPEN_STALL_RCA_2026_10_05.md). When the index can’t serve such a read, read_range answers with an error instead; the pane falls back to its short tail read, which extends the index again.