Stub-archive rule: 100 MB cap on every leg, ROT13 volume names are volumes

The first five hours in production (LOG.md (128)) dropped 522 passworded
videos of one a.b.erotica poster: ROT13-named volumes (".cnegN.rar" is
".partN.rar") of 1-270 MB in 258 kB articles to two groups, which the
article-size leg took for stubs. The cap that X and W already had now
applies to A as well (the catalog sample has 6 A-leg hits over 100 MB,
4 of them exe-only), and a ROT13 volume name is no single archive.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

REBUILD.md

@@ -787,11 +787,13 @@ par2 can still join an open one; the start edge doesn't count, since a par2
 follows its rar and 7% of the catalog's releases are start edges). A settled
 release of one unsplit zip, rar or 7z and nothing else is dropped as a
 **stub archive** (`stub-archive`, key: the legs tripped) when posted to
-2+ groups and (A) its articles are ≤ 256 KiB with the release ≥ 1 MB
-(Power-Post's 250 kB default; a one-article release always has small
-articles, which exempts e-books and sidecars), or (X) posted to 4+ groups,
-or (W) by a webmail poster, X and W under 100 MB (the fakes stop at
-~90 MB; hash-named uploads and real albums above it don't). A release
+2+ groups, under 100 MB (the fakes stop at ~90 MB; hash-named uploads,
+real albums and passworded videos above it don't), and (A) its articles
+are ≤ 256 KiB with the release ≥ 1 MB (Power-Post's 250 kB default; a
+one-article release always has small articles, which exempts e-books and
+sidecars), or (X) posted to 4+ groups, or (W) by a webmail poster. A
+ROT13 volume name (".cnegN.rar" is ".partN.rar": a.b.erotica's passworded
+videos, LOG.md (128)) is a volume, not a single archive. A release
 touching a music, e-book, comics, tabs or fonts group is exempt: those
 communities post real single small archives the same way (karaoke zips to
 a.b.sounds.karaoke + a.b.test with Power-Post's articles; 16 of 32,308