Numbered items of a set don't take the poster-tag rule

"ai-engineer-complete [401/465] - \"003 Defining Tools with JSON
Schema.mp4\"": the subject's text shares no word with the lesson's
descriptive name, so it was taken for a poster's constant tag and each of
the course's 465 files keyed a release of its own (releases 75941915,
75941916). A stem starting with a 1-3 digit index and a separator is an
item of a set the subject names, as audio tracks and images already
were; uploads hours apart stay apart by the re-upload rule. Both
implementations; tests; fixtures identical.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

lib/release/identity.ts

@@ -209,8 +209,11 @@ export function releaseIdentity(input: ReleaseInput): ReleaseIdentity | null {
   // release the file is (LOG.md 2026-10-09 (8)). Only when the stem itself describes something
   // ("Cephalgy.-.Weisses.Fleisch.2003", not a scene abbreviation like "grp-sm" under
   // "Some.Movie.2008-GRP", nor "file_id.diz"), and not for images and audio tracks, which the
-  // subject names as a set or album ("IMG_3086.jpg", "072 - Die Teufelsuhr.MP3").
-  const tag = !image && !AUDIO.test(input.name) && describes(stem) && !looksRandom(stem) && isPosterTag(remainder, stem)
+  // subject names as a set or album ("IMG_3086.jpg", "072 - Die Teufelsuhr.MP3"), nor for numbered items of
+  // a set ("ai-engineer-complete [401/465] - "003 Defining Tools with JSON Schema.mp4"": a course's 465
+  // lessons were releases of their own; LOG.md 2026-10-11 (7)). Uploads hours apart are apart anyway.
+  const numbered = /^\d{1,3}[ ._-]/.test(stem)
+  const tag = !image && !numbered && !AUDIO.test(input.name) && describes(stem) && !looksRandom(stem) && isPosterTag(remainder, stem)
   // An image set without a counter: the image's name up to its last number, without numbers
   // ("Kitchen Hottie 1 set233-76-lg" → "Kitchen Hottie set", "bm_jessica_blb_h087" → "bm jessica blb h").
   const prefix = image ? stem.replace(/\d+\D*$/, '').replace(/\d+/g, ' ').replace(/[\s._-]+/g, ' ').trim() : ''