sec05: EN downloads complete (30 files) + SUMMARY at-a-glance + lgdl queue infra

- 30/31 EN candidates downloaded via libgen, all content-verified
  (magic+pages+first-page text); 08b 37-pp fragment discarded
- EN gaps: 04/05/15/16/23 not found (rare academic), 03/14 ia-restricted
- MANIFEST.md: EN sections per item + not-downloadable extended
- 26 cards: Downloads tables w/ EN rows + EN NOT FOUND notes (6 cards)
- SUMMARY.md created (canon v1): at-a-glance table 29 items, EN->RU authors
- tools/lgdl.py: speed-probe + CDN-edge re-draw (per-request get.php
  302s to different storage hosts), connect timeout, stall wipe on first stall
- AGENTS.md: Lesson 9 (EN-queue infra: ads.php throttle, watchdog,
  unbuffered logs, dual-queue trap, AA 403, i2p verdict)

sections/05-ethnology/17-stevens-two-million-year-old-self.md

@@ -18,6 +18,12 @@
 | Самость, которой два миллиона лет | Клуб Касталия (М.) | 2021 | — | — | 978-5-521-15867-6 |
 
 
+## Downloads
+
+| lang | file | size | source |
+|------|------|------|--------|
+| EN | 17-stevens-two-million-year-old-self-en-2005.pdf | 18.3 MB | lg f/91578760 (163 pp, scan) |
+
 ## Catalog records
 
 РГБ 0 · МГУ 0 (verified 2026-09-21; Касталия малотиражное); данные: labirint book 794734 + OZON (user tip)