Rebuild: completeness as indexed, file totals from any counter, pausable tails, progress by articles

- releases.complete is computed with every batch (files >= the
  counter's total) instead of only when a release settles after 6 quiet
  hours: the 'complete' filter matched nothing in a fresh catalog.
- A release's file total comes from any counter form (counterTotal:
  '(01/10)', 'File 27 of 132', …), not only [i/M]; the post rule's key
  keeps the [i/M] total, so keys are unchanged. Both implementations.
- groups.tail: a group's live tail can be paused (its history and owner
  priority stay), e.g. to let other groups' history go first.
- Stats: history by articles, and the current pass (history ranges
  before those deferred 2000 priorities behind) as its own figure; the
  header showed 0.1% of ranges counting 145k deferred ones.

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

database/migrations/1770000001300_groups_tail.ts

@@ -0,0 +1,15 @@
+import { BaseSchema } from '@adonisjs/lucid/schema'
+
+/**
+ * A group's live tail can be paused (its history and its place in the owner
+ * rule stay): e.g. to let other groups' history go first.
+ */
+export default class extends BaseSchema {
+  async up() {
+    this.schema.raw(`ALTER TABLE groups ADD COLUMN IF NOT EXISTS tail boolean NOT NULL DEFAULT true`)
+  }
+
+  async down() {
+    this.schema.raw(`ALTER TABLE groups DROP COLUMN IF EXISTS tail`)
+  }
+}