nx_galx_sortindex.nx

nx_galx_sortindex.nx -- LIBRARY (no main -> build the _gate): build a SORT-INDEX over the gallery's recordings so the daemon can SORT BY an integer key (runtime, file-size, view-count, rating) at O(1)-per-page instead of re-sorting every request (operator: "slow to sort"). R2 of the s-class media-UI epic. Composes with the R1 discovery offset (gs_eff_offset): the serve reads this index forward (ascending) or backward (descending) and paginates with the SAME pct/rand/offset logic, so a single ascending index serves both sort directions. FORMAT (big-endian u64 so the daemon reads it with the existing gs_rb64; SAME shape as the category index galx_cat_<c>.bin so the serve reuses that reader): [0..8) stamp = byte-size of the freshness file (vid_paths.tsv) -> stale-detect / rebuild-on-change [8..16) count N [16..) N x id = recording ids (0-based line numbers) sorted ASCENDING by key The KEY comes from a "key file": one record per line, key = the first run of decimal digits on that line. So it ingests nx_galx_durindex's out_dur.raw "dur_ms=<n>" lines directly, and any future size / view-count key file. Line index i == recording id i (matches the daemon's id->line mapping); a blank or key-less line becomes key 0 (keeps id alignment) and simply sorts first. license_tier: ORIGINAL