Restores H-Z tune audio previously absent from the ingested data.
Sources: Cyber Hymnal (http://www.hymntime.com/tch) MIDI library,
matched by tune name to each BLB hymn page's Music attribution.
Also restores empty mid_d_daystar.mid from the Day-Star tune.
Original gap: 1,463 missing files / 1,925 broken pages.
After recovery: 661 still missing (modern gospel tunes absent from cyber hymnal).
All files validated as Standard MIDI (MThd).
