Expand terminal filesystem, add mainframe hint cron, redirect PHP logs

- Game1 terminal: flesh out the virtual filesystem with a realistic
  spread of Linux directories/files (~70 dirs, ~140 files) so it no
  longer reads as an obviously small puzzle set, without touching any
  win-condition or rapport files.
- Add app:hints:check command + a php-cron container (BusyBox crond)
  that nudges players who haven't contacted every teammate 5 minutes
  into a session, via a new 'hint' Mercure message type.
- Log the cron command's output to var/log/cron/cron.log and rotate
  it (25MB / 90 days) via logrotate, run daily from the same crontab.
- Redirect PHP's error_log and Symfony's prod app/deprecation logs
  from stderr-only into var/log/php/*.log (kept alongside stderr),
  with the same rotation policy.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

assets/game1/filesystem/etc/passwd

@@ -0,0 +1,11 @@
+root:x:0:0:root:/root:/bin/bash
+daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
+bin:x:2:2:bin:/bin:/usr/sbin/nologin
+sys:x:3:3:sys:/dev:/usr/sbin/nologin
+sync:x:4:65534:sync:/bin:/bin/sync
+mail:x:8:8:mail:/var/mail:/usr/sbin/nologin
+www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin
+backup:x:34:34:backup:/var/backups:/usr/sbin/nologin
+sshd:x:105:65534::/run/sshd:/usr/sbin/nologin
+admin:x:1000:1000:admin,,,:/home/admin:/bin/bash
+guest:x:1001:1001:guest,,,:/home/guest:/bin/bash