Rebuild: an image without words around it is keyed as a stem

So a cover 'x.jpg' joins 'x.part01.rar' in a stem-named post; an image
set like 'IMG_008' keys as the stem 'IMG'. Both implementations.

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

lib/release/identity.ts

@@ -226,8 +226,8 @@ export function releaseIdentity(input: ReleaseInput): ReleaseIdentity | null {
   if (!tag && fileTotal && isPostToken(remainder)) {
     return { key: hash('post', input.poster, remainder, fileTotal), name: remainder, fileTotal, source: 'post' }
   }
-  // An image without words around it: its set by its name.
-  if (image) return { key: hash('images', input.poster, prefix), name: prefix || stem, fileTotal, source: 'stem' }
+  // An image without words around it: its set by its name (keyed as a stem, so "x.jpg" joins "x.part01.rar").
+  if (image) return { key: hash('stem', input.poster, prefix || stem), name: prefix || stem, fileTotal, source: 'stem' }
   // The [i/M] total is informational, not part of the key: posters often
   // upload the par2 index without a counter, and it belongs to the same post.
   return { key: hash('stem', input.poster, stem), name: stem, fileTotal, source: 'stem' }

tests/unit/release/identity.spec.ts

@@ -229,5 +229,7 @@ test.group('release / par2 names', () => {
     const par2 = id('(Geisterjäger John Sinclair Hörspiele Vol. 2) [59/59] - "Hörspiele Vol. 2.par2" yEnc', 'Hörspiele Vol. 2.par2')
     assert.equal(t1.key, t2.key)
     assert.equal(t1.key, par2.key)
+    // A cover without words around it joins its stem's archive.
+    assert.equal(id('[2/6] - "x.jpg" yEnc', 'x.jpg').key, id('[1/6] - "x.part01.rar" yEnc', 'x.part01.rar').key)
   })
 })

tools/edge-bench-rs/src/names.rs

@@ -534,7 +534,7 @@ pub fn release_identity(poster: &str, subject: &str, name: &str) -> Release {
     }
     if image {
         let name = if prefix.is_empty() { stem.clone() } else { prefix.clone() };
-        return Release { key: hash(&["images", poster, &prefix]), name, source: "stem", file_total };
+        return Release { key: hash(&["stem", poster, &name]), name, source: "stem", file_total };
     }
     Release { key: hash(&["stem", poster, &stem]), name: stem, source: "stem", file_total }
 }
@@ -947,6 +947,8 @@ mod tests {
         let par2 = id(r#"(Geisterjäger John Sinclair Hörspiele Vol. 2) [59/59] - "Hörspiele Vol. 2.par2" yEnc"#, "Hörspiele Vol. 2.par2");
         assert_eq!(t1.key, t2.key);
         assert_eq!(t1.key, par2.key);
+        // A cover without words around it joins its stem's archive.
+        assert_eq!(id(r#"[2/6] - "x.jpg" yEnc"#, "x.jpg").key, id(r#"[1/6] - "x.part01.rar" yEnc"#, "x.part01.rar").key);
     }
 
     #[test]