Rebuild: re-uploads are releases of their own

A poster re-uploading under the same name made one release of all
uploads: in a sample, 24% of releases with 2+ files had a file name more
than once (4.3% of files extra copies), 70% of those copies posted a day
or more apart; their NZBs listed each copy.

- File assembly keeps a re-upload's copy apart: a part already in every
  open copy, posted more than 3 h from them, starts another copy; a
  missing part fills the nearest copy (a re-send of what was missing),
  a re-sent part near a copy that has it is ignored as before.
- A key's files in a batch split into uploads where posting pauses for
  more than 3 h, counted from the latest article posted so far (a file
  that takes hours to post doesn't split it); each upload is judged and
  chunked on its own (ReleaseChunk.upload, .postedLast; candidates carry
  their upload).
- The catalog matches a chunk to the release of its key whose articles
  the range's group owns and whose posting window is within 3 h, else
  starts one (key, key:2, …): releases get identity_key, group_id,
  last_posted_at. Keys are locked in order (advisory locks), so
  concurrent batches neither deadlock nor both start one; the merger
  writes in key order too. The same upload multi-posted to other groups
  is a release per group.
- The gap: 91% of uploads post within 3 h; 73% of re-uploaded copies
  come later (releases:upload-gaps). releases:duplicates measures the
  duplicate names.

Both implementations; check.ts compares the windows and uploads too
(identical on all captures; Rust tests mirror the TypeScript cases).

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

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

@@ -72,7 +72,7 @@ fn dump_batch(batch: &Batch, out: &mut impl Write) {
     line.push_str(&format!("{{\"t\":\"b\",\"from\":{},\"next\":{},\"headers\":{}}}", batch.from, batch.next, batch.headers));
     emit(&mut line);
     let release = |r: &indexer::ReleaseChunk, kind: &str, line: &mut String| {
-        line.push_str(&format!("{{\"t\":\"{kind}\",\"key\":"));
+        line.push_str(&format!("{{\"t\":\"{kind}\",\"upload\":{},\"key\":", r.upload));
         json_str(&r.key, line);
         line.push_str(",\"name\":");
         json_str(&r.name, line);
@@ -89,6 +89,8 @@ fn dump_batch(batch: &Batch, out: &mut impl Write) {
         }
         line.push_str("],\"postedAt\":");
         opt_num(r.posted_at, line);
+        line.push_str(",\"postedLast\":");
+        opt_num(r.posted_last, line);
         line.push_str(&format!(
             ",\"files\":{},\"segments\":{},\"bytes\":{},\"firstArticle\":{},\"lastArticle\":{},\"readable\":{},\"hasPar2\":{},\"payload\":\"{}\"",
             r.files,
@@ -114,7 +116,7 @@ fn dump_batch(batch: &Batch, out: &mut impl Write) {
         emit(&mut line);
     }
     for c in &batch.candidates {
-        line.push_str("{\"t\":\"c\",\"releaseKey\":");
+        line.push_str(&format!("{{\"t\":\"c\",\"upload\":{},\"releaseKey\":", c.upload));
         json_str(&c.release_key, &mut line);
         line.push_str(&format!(",\"kind\":\"{}\",\"messageId\":", c.kind));
         json_str(&c.message_id, &mut line);