Rebuild: the live tail

coordinator:run plans the articles after each group's last range every
TAIL_EVERY_SECONDS (120): one LIST ACTIVE per name prefix gives every
group's newest article, and new articles become ranges at priority -1,
leased and prefetched before any history. A group gets a tail range once
it has TAIL_MIN_ARTICLES (100k, a chunk) new or its last planning is
TAIL_MAX_DELAY_MINUTES (15) ago, so quiet groups don't make a range every
round. History (planAll, hourly) is now only for groups not planned yet.
ranges:plan --tail plans one round.

Found on the way: with XFEATURE COMPRESS GZIP on, Eweka compresses LIST
ACTIVE's reply too ("215 NewsGroups Follow [COMPRESS=GZIP]"), and
listActive waited for a plain end that never came (groups:add --top too).
It reads the compressed reply now; the fake server in the test does both.

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

commands/ranges_plan.ts

@@ -1,18 +1,21 @@
-import { BaseCommand } from '@adonisjs/core/ace'
+import { BaseCommand, flags } from '@adonisjs/core/ace'
 import type { CommandOptions } from '@adonisjs/core/types/ace'
 import Planner from '#services/planner'
 import NntpPool from '#services/nntp_pool'
 
-/** Cuts every active group's history (and new articles since) into ranges. */
+/** Cuts new groups' history into ranges, or (--tail) plans one round of the live tail. */
 export default class RangesPlan extends BaseCommand {
   static commandName = 'ranges:plan'
-  static description = "Plans ranges for the indexed groups' articles"
+  static description = "Plans ranges for new groups' history, or one round of the live tail"
   static options: CommandOptions = { startApp: true }
 
+  @flags.boolean({ description: 'Plan the live tail once (what coordinator:run does every few minutes)' })
+  declare tail: boolean
+
   async run() {
     try {
-      const { groups, ranges } = await Planner.planAll()
-      this.logger.info(`${ranges} ranges planned over ${groups} groups.`)
+      const { groups, ranges } = this.tail ? await Planner.planTail() : await Planner.planAll()
+      this.logger.info(`${ranges} ${this.tail ? 'tail ' : ''}ranges planned over ${groups} groups.`)
     } finally {
       await NntpPool.close()
     }