The Rust worker is the product: edge/, built and checked in CI

User: Rust is the product (option a). tools/edge-bench-rs moves to edge/
(crate edge; binaries edge-node, the worker, and edge-bench, the replay).
CI's new job edge runs cargo test and edge/check-fixtures.sh: both
RangeIndexers on three committed captures (edge/fixtures, 25k overview
lines each of a.b.models, a.b.ath and a.b.boneless in 5 chunks, 3.5 MB),
compared field by field with check.ts; deploy waits for it. The
TypeScript RangeIndexer stays as check.ts's reference. README: what it
is now; the benchmark findings as history.

Random names: looksRandom missed long tokens of capitals and digits
("51294P1CUKR2R35X", release 74539068, readable and a Newznab title).
12+ capitals and digits switching 6+ times between them are random
(COD4MW2REMASTERED switches 4 times, BEATLES1964REMASTER twice); both
implementations, identical on the fixtures.

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

lib/release/random.ts

@@ -5,6 +5,17 @@ import { isGenericName } from './identity.js'
  * separators, and the other generated shapes seen on Usenet (LOG.md
  * 2026-10-01 (3)). Kept in step with SQL's is_readable_name().
  */
+/** How often a token goes from a letter to a digit or back. */
+function letterDigitSwitches(token: string): number {
+  let switches = 0
+  for (let i = 1; i < token.length; i++) {
+    const a = token.charCodeAt(i - 1) <= 57
+    const b = token.charCodeAt(i) <= 57
+    if (a !== b) switches++
+  }
+  return switches
+}
+
 export function looksRandom(name: string): boolean {
   // An unknown short extension (e.g. ".bin") says nothing about the name.
   name = name.replace(/\.[A-Za-z0-9]{1,4}$/, '')
@@ -21,6 +32,9 @@ export function looksRandom(name: string): boolean {
   if (/^[a-z0-9]{12,}$/.test(name) && (name.match(/\d/g)?.length ?? 0) >= 2 && (name.match(/[a-z]/g)?.length ?? 0) >= 4) return true
   // wHJ7s71sAGE: short, but capitals all over the token, not only at word starts
   if (/^[A-Za-z0-9]{8,15}$/.test(name) && /\d/.test(name) && /[a-z]/.test(name) && (name.slice(1).match(/[A-Z]/g)?.length ?? 0) >= 3) return true
+  // 51294P1CUKR2R35X: capitals and digits only, switching between them all over the token
+  // (COD4MW2REMASTERED switches 4 times, BEATLES1964REMASTER twice).
+  if (/^[A-Z0-9]{12,}$/.test(name) && letterDigitSwitches(name) >= 6) return true
   if (!/^[A-Za-z0-9]{16,}$/.test(name) || !/[a-z]/.test(name) || !/[A-Z]/.test(name)) return false
   // Digits, or many capitals without separators (e.g. RmISakytFwXSCEzjVEpaKk).
   return /\d/.test(name) || (name.match(/[A-Z]/g) ?? []).length >= 6