Pending ladder by class, twins by content, dropped classes at the edge

The prober names 6% of the unnamed releases it finishes and the pending
queue (44M) grows eleven times faster than it probes. A sample of 44,530
finished pending rows shows the headers predict a name: size bucket, name
shape, completeness, tool and group separate 0% classes from 95% ones,
while the learner keyed on tool and group alone (LOG.md (130)).

- lib/release/classes.ts, names::pending_class, SQL pending_class():
  a release's class (size × shape × partial, 1..70), the three in step.
- Migration 6800: pending_releases.klass and target_bytes (the first
  target's article; candidates carry bytes now), pending_classes with
  each class's climbs, names, waiting and verdict, the claim's index.
- The ladder claims the classes with the best record first (a prior for
  the unexplored, at most a quarter of a claim from one), the cheapest
  target first within one, then the oldest of the rest; records classes
  like signatures and drops them at the same thresholds; discards their
  waiting releases. Claimed rows sorted in code: an UPDATE returns none.
- The rule set's droppedClasses: the edge keeps unnamed releases of a
  dropped class out of the pending store (counted as garbage), the
  explored sample excepted.
- hash_twins.ts: a probed file whose first 16 KiB and size match a named
  catalog release's names a pending release the probe didn't, and sets
  the inner name of a catalog release without one.
- pending:classes classes the rows from before and seeds the record from
  the finished ones; rules:classes publishes the dropped classes;
  releases:readable also marks the rows' candidates unreadable.

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

tests/unit/release/classes.spec.ts

@@ -0,0 +1,22 @@
+import { test } from '@japa/runner'
+import { classKey, describeClass, pendingClass } from '#lib/release/index'
+
+test.group('release / pendingClass', () => {
+  test('size bucket × name shape × partial, as names.rs pending_class', ({ assert }) => {
+    // The same cases as the Rust test.
+    assert.equal(pendingClass('c04212a389cf69edc54767355ab5285f', 5_000_000, false), 15)
+    assert.equal(pendingClass('c04212a389cf69edc54767355ab5285f', 5_000_000, true), 16)
+    assert.equal(pendingClass('Zx5AjNaK-mh7CFg6Hf8uu', 500_000_000, false), 3 * 14 + 5 * 2 + 1)
+    assert.equal(pendingClass('1650777167', 100, false), 3)
+    assert.equal(
+      pendingClass('mrrtmzrzmi4dgmrzmyytqmlbztczbx', 2_000_000_000, false),
+      4 * 14 + 2 * 2 + 1
+    )
+    assert.equal(pendingClass('PsNdnYiugfZ.rar', 20_000_000, false), 2 * 14 + 3 * 2 + 1)
+    assert.equal(pendingClass('n5d1ueIf34X', 20_000_000, true), 2 * 14 + 4 * 2 + 2)
+    assert.equal(pendingClass('sgkra vU7u2yuw9LDLCjDu04pOez', 999, false), 13)
+    assert.equal(describeClass(16), '1-10M hex partial')
+    assert.equal(describeClass(3 * 14 + 5 * 2 + 1), '100M-1G separators')
+    assert.equal(classKey('nyuu', 'alt.binaries.boneless', 16), 'nyuu\talt.binaries.boneless\t16')
+  })
+})