content audit sec01-06: fixes (audit_content.py + 12 file/card corrections)

- tools/audit_content.py: per-file vs item-title triage (SUSPECT/SMALL/NO-TEXT/NO-CYR)
- sec01: .part removed; 10 files restored .pdf ext (LFS rename); #04/#19/#27 verify notes
- sec02 #16: corrupted double-encoded txt -> clean flib fb2 b/844509; #17/#22 doc verified via catdoc
- sec03 #11: -b epub = Spanish von Franz (Paidós 1983, forged EN OPF) -> bonus label
- sec03 #42: КАРО 2012 'Irish Tales' = EN reader (not RU, not the listed book) -> bonus rename
- sec03 #56: Onians b/c/d/e = Cambridge 24-87KB previews -> labeled
- sec06 #18: filename 1981->1989 (Perera 'Descent to the Goddess' 1989; 1981 = other book)
- sec06 #28: ia Zimmer OCR layer = foreign Devanagari text; images = RKP (p.100 verified)
- sec04 #30: buksmart 2020 = RU/FR bilingual w/ VeryPDF watermarks -> note
- linter: azw3/mobi ext + underscore in fname regex; manifest cross-check ignores off-disk rows;
  8 legacy cards section-order fixed (CR before DL)
- AGENTS.md: 'Content audit (2026-09-25)' lessons section
- check-md: 0/219

tools/check-md.py

@@ -63,9 +63,9 @@ def lint_card(path, manifest_files):
     # Downloads table cross-check
     dm = re.search(r'^## Downloads\n(.*?)(?=^## |\Z)', c, re.M | re.S)
     if dm:
-        rows = re.findall(r'^\|\s*(EN|RU\??|\?)\s*\|\s*([0-9]{2}-[a-zA-Z0-9\.\-]+)\s*\|', dm.group(1), re.M)
+        rows = re.findall(r'^\|\s*(EN|RU\??|\?)\s*\|\s*([0-9]{2}-[a-zA-Z0-9_\.\-]+)\s*\|', dm.group(1), re.M)
         disk = set(os.path.basename(f) for f in glob.glob(f"downloads/{sec_of(path)}/*"))
-        manifest = set(f for f, _, _ in manifest_files.get(num, []))
+        manifest = set(f for f, _, _ in manifest_files.get(num, []) if f in disk)  # skip legacy/renamed rows
         for lang, fname in rows:
             if fname not in disk:
                 issues.append(f'Downloads file not on disk: {fname}')