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>

lib/nntp/xover_client.ts

@@ -105,7 +105,9 @@ export class XoverClient {
     return this.timed(async () => {
       const reply = await this.command(`LIST ACTIVE ${pattern}`)
       await this.expect(reply, ['215'])
-      return (await this.plainBody())
+      // With XFEATURE COMPRESS GZIP on, Eweka compresses this list too ("215 NewsGroups Follow [COMPRESS=GZIP]").
+      const body = reply.includes('COMPRESS=GZIP') ? (await this.compressedRaw(true)).text : await this.plainBody()
+      return body
         .split('\r\n')
         .filter(Boolean)
         .map((line) => {