nntp:probe: shows the bytes a stalled reply left

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

commands/nntp_probe.ts

@@ -95,7 +95,7 @@ export default class NntpProbe extends BaseCommand {
     } catch (error: any) {
       const timedOut = /timed out/i.test(error.message)
       this.logger.warning(
-        `  XOVER ${from}-${to}: ${error.message} after ${Date.now() - startedAt} ms${client ? `, ${client.buffered} bytes buffered` : ''}`
+        `  XOVER ${from}-${to}: ${error.message} after ${Date.now() - startedAt} ms${client ? `, ${client.buffered} bytes buffered: ${JSON.stringify(client.bufferedHead().toString('latin1'))} (${client.bufferedHead().toString('hex')})` : ''}`
       )
       return timedOut
     } finally {