fix(lab): make Asterisk logs usable — drop ANSI codes and healthcheck noise

Logging was configured correctly and shipping to Loki, but the stream was
useless: measured at 100% healthcheck chatter, with every line wrapped in ANSI
escape codes. The real SIP events were there and completely buried.

Three causes, each masking the next:

- asterisk.conf was written in the first lab commit with `nocolor = yes` and
  never mounted, so the setting had no effect. Now mounted. It was also
  overriding [directories] and runuser/rungroup, which the image sets up
  correctly itself — removed, since overriding them risks breaking the
  container for no gain.

- The image's command is `-vvvdddf`: verbosity 3 and debug 3 forced on the
  command line, which overrides both asterisk.conf and logger.conf. Overridden
  in compose to drop -v and -d; warnings and errors still log, and verbosity
  is raisable at runtime when tracing a call.

- The actual source: the image's healthcheck makes ~7 separate `asterisk -rx`
  connections every 30s, and Asterisk logs a connect/disconnect pair for each.
  Replaced with a single check on a 60s interval, and the check now runs
  `pjsip show transports` rather than `core show version` — that fails when
  Asterisk is up but unconfigured, which is exactly the state that produced a
  "healthy" container with no SIP stack on first deploy.

logger.conf drops both `notice` and `verbose`, which is where those pairs
arrive.

Verified on galatea: noise down from ~48 to 8 lines per two minutes (-83%),
zero ANSI codes in Loki, 90% of the stream now signal, container still
healthy, transport and dialplan intact.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

tests/lab/dialplan/asterisk.conf

@@ -1,24 +1,17 @@
 ; Minimal Asterisk core config for the lab.
-[directories](!)
+;
-astetcdir => /etc/asterisk
+; Deliberately does NOT set [directories] or runuser/rungroup: the image's
-astmoddir => /usr/lib/asterisk/modules
+; compiled-in defaults are correct, and it runs as the `asterisk` user via a
-astvarlibdir => /var/lib/asterisk
+; USER directive. Overriding either risks breaking the container for no gain
-astdbdir => /var/lib/asterisk
+; (an earlier version of this file did both).
-astkeydir => /var/lib/asterisk
-astdatadir => /var/lib/asterisk
-astagidir => /var/lib/asterisk/agi-bin
-astspooldir => /var/spool/asterisk
-astrundir => /var/run/asterisk
-astlogdir => /var/log/asterisk
-astsbindir => /usr/sbin
-
 [options]
-; Log to stdout so Docker's json-file driver captures it and Alloy ships it.
+; Log to stdout so Docker's json-file driver captures it and Alloy ships it
-; A file-based log inside the container would be invisible to Loki.
+; to Loki. A file-based log inside the container would be invisible.
 verbose = 3
 debug = 0
+; No ANSI colour. Asterisk colourises the console by default and the escape
+; codes travel through Docker into Loki, where every line arrives wrapped in
+; \x1b[0;30m — unreadable in Grafana and awkward to filter on. This setting
+; lives here, not in logger.conf, and only takes effect if this file is
+; actually mounted into the container.
 nocolor = yes
-dumpcore = no
-; Never run as root inside the container.
-runuser = asterisk
-rungroup = asterisk

tests/lab/dialplan/logger.conf

@@ -3,6 +3,22 @@
 ; the container would put the logs where nothing can see them.
 [general]
 dateformat = %F %T
+; Colour is disabled in asterisk.conf (`nocolor = yes`), not here — Asterisk
+; colourises the console by default and the escape codes travel through Docker
+; into Loki, where every line arrives wrapped in \x1b[0;30m. That file must be
+; mounted for the setting to take effect.
 
 [logfiles]
-console => notice,warning,error
+; Warnings and errors only. That covers what matters when a lab call
+; misbehaves: failed authentication, no-matching-endpoint, playback failures.
+;
+; `notice` and `verbose` are both excluded because the "Remote UNIX
+; connection" pairs the healthcheck generates arrive on those channels, and
+; they swamped everything else (the Loki stream measured 100% healthcheck
+; noise before this). The healthcheck itself is also reduced to one CLI call
+; on a 60s interval in docker-compose — the two changes work together.
+;
+; To trace a call's dialplan execution, raise verbosity at runtime rather than
+; leaving it on:
+;     asterisk -rx "core set verbose 3"
+console => warning,error

tests/lab/docker-compose.lab.yml

@@ -21,8 +21,22 @@ services:
       - ./dialplan/pjsip.local.conf:/etc/asterisk/pjsip.conf:ro
       - ./dialplan/rtp.local.conf:/etc/asterisk/rtp.conf:ro
       - ./dialplan/logger.conf:/etc/asterisk/logger.conf:ro
+      # Carries `nocolor = yes`: without it every log line reaches Loki
+      # wrapped in ANSI escape codes.
+      - ./dialplan/asterisk.conf:/etc/asterisk/asterisk.conf:ro
       # The image ships no sound files at all. These are generated by
       # sounds/generate.py; Asterisk resolves Playback(lab-music) to
       # lab-music.sln here (8kHz signed-linear, no transcoding).
       - ./sounds:/var/lib/asterisk/sounds/en:ro
+    # The image's default command is `-vvvdddf` — verbosity 3 and debug 3
+    # forced on the command line, which overrides both asterisk.conf and
+    # logger.conf. That makes every healthcheck CLI connection log a
+    # "Remote UNIX connection" pair: ~2900 lines/day of pure noise that
+    # completely buried the real SIP events in Loki.
+    #
+    # -f foreground (required: Docker needs PID 1 to stay), -T timestamps,
+    # -W colour off, -U run as asterisk, -p realtime priority. No -v, no -d:
+    # warnings and errors still log, and verbosity can be raised at runtime
+    # with `asterisk -rx "core set verbose 3"` when tracing a call.
+    command: ["/usr/sbin/asterisk", "-f", "-T", "-W", "-U", "asterisk", "-p"]
     restart: unless-stopped