Complete archive listings by walking RAR headers, at low priority

Inspection lists only the entries whose headers are in the first segment
of a first volume. A walk hops from header to header, fetching one segment
per entry and volume, in its own queue (one job per collection worker) on
NNTP connections inspection isn't waiting for. content:walk-archives queues
releases inspected earlier (CONCEPT D40).

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

database/schema.ts

@@ -411,7 +411,7 @@ export class ReleaseFileSchema extends BaseModel {
 }
 
 export class ReleaseSchema extends BaseModel {
-  static $columns = ['category', 'complete', 'container', 'contents', 'encrypted', 'extensions', 'fileCount', 'fileTotal', 'firstSeenAt', 'groups', 'id', 'lastSeenAt', 'name', 'password', 'passwordSource', 'postedAt', 'poster', 'releaseKey', 'searchFiles', 'searchText', 'size', 'source'] as const
+  static $columns = ['category', 'complete', 'container', 'contents', 'contentsWalkedAt', 'encrypted', 'extensions', 'fileCount', 'fileTotal', 'firstSeenAt', 'groups', 'id', 'lastSeenAt', 'name', 'password', 'passwordSource', 'postedAt', 'poster', 'releaseKey', 'searchFiles', 'searchText', 'size', 'source'] as const
   $columns = ReleaseSchema.$columns
   @column()
   declare category: number | null
@@ -421,6 +421,8 @@ export class ReleaseSchema extends BaseModel {
   declare container: string | null
   @column()
   declare contents: any | null
+  @column.dateTime()
+  declare contentsWalkedAt: DateTime | null
   @column()
   declare encrypted: boolean | null
   @column()