data(bible): add LXXE 27k (Brenton 1851) + source column (MT/GNT) — no info lost

- verses: NKJV 31102 + LXXE 27058 (import_brenton_septuagint.py via
  eBible.org eng-Brenton_usfm.zip, version='LXXE') — primary OT English
  for ot_source=lxx (src/main.zig:417), matches docs/DB_SHARDING.md
  shard verses.lxxe.db (primary) vs verses.nkjv.db (buried).
- interlinear: backfill source MT/GNT (migrate_add_interlinear_source.py)
  233343 MT + 4985 GNT, rebuild idx_interlinear_unique to include source
  so future LXX scrape (cache_lxx_interlinear.py 432k) won't clobber.
- file 31M → 43M, still < GitHub 100M, tracked via !data/bible.db
  (see .gitignore:48). Full 118M with LXX interlinear pending
  cache_lxx_interlinear.py scrape.

Preserves 551-line portal + Universal Corpus + new Learn→Docs flow —
push all dat as requested.

Author: github-actions[bot]