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>

docker/php/logrotate/cron-hints.conf

@@ -0,0 +1,11 @@
+/var/www/html/var/log/cron/cron.log {
+    size 25M
+    rotate 100
+    maxage 90
+    missingok
+    notifempty
+    compress
+    delaycompress
+    dateext
+    dateformat -%Y%m%d-%s
+}