build(playout): compose wiring + .env knobs

- Add /mnt/NVME/MAM/wild-dragon-media:/media to mam-api (rw) and worker-p4
  (rw); web-ui (ro, for serving HLS preview segments).
- worker-p4 WORKER_QUEUES gains 'playout-stage' so master-tier nodes pick up
  the loudnorm stage jobs (they already have ffmpeg + the media mount).
- New build-only 'playout' service with profile ["build-only"] so
  `docker compose --profile build-only build playout` produces the
  wild-dragon-playout:latest image without compose trying to up it as a
  long-running service. mam-api spawns these on demand.
- mam-api env adds PLAYOUT_IMAGE + PLAYOUT_AMCP_BASE_PORT (5250 default).
- .env.example: PLAYOUT_IMAGE, PLAYOUT_AMCP_BASE_PORT.

.env.example

@@ -63,3 +63,10 @@ GOOGLE_ALLOWED_DOMAIN=
 # Note: if a Google-linked account also has TOTP enabled, sign-in still requires
 # the authenticator code (Google is treated as the first factor). Accounts without
 # TOTP complete sign-in in one Google step.
+
+# Playout / Master Control (MCR)
+# Image tag the mam-api spawns when a channel starts. Build with:
+#   docker compose --profile build-only build playout
+PLAYOUT_IMAGE=wild-dragon-playout:latest
+# Base AMCP port — each channel binds to BASE + channel_id (in CasparCG terms).
+PLAYOUT_AMCP_BASE_PORT=5250

docker-compose.yml

@@ -40,6 +40,7 @@ services:
       - /var/run/docker.sock:/var/run/docker.sock
       - /mnt/NVME/MAM/wild-dragon-live:/live
       - /mnt/NVME/MAM/wild-dragon-growing:/growing
+      - /mnt/NVME/MAM/wild-dragon-media:/media
       - /mnt/NVME/MAM/sdk:/sdk
       - /dev/shm:/dev/shm
       - /run/dbus:/run/dbus
@@ -61,6 +62,8 @@ services:
       NODE_IP: ${NODE_IP}
       NODE_HOSTNAME: ${NODE_HOSTNAME:-}
       CAPTURE_TOKEN: ${CAPTURE_TOKEN}
+      PLAYOUT_IMAGE: ${PLAYOUT_IMAGE:-wild-dragon-playout:latest}
+      PLAYOUT_AMCP_BASE_PORT: ${PLAYOUT_AMCP_BASE_PORT:-5250}
     deploy:
       resources:
         reservations:
@@ -120,14 +123,16 @@ services:
       # after the capability-routing split, so import jobs sat unprocessed and
       # assets stayed `ingesting` forever. import is concurrency-1 + network-
       # bound, so one consumer (this heavy/primary worker) is sufficient.
-      WORKER_QUEUES: proxy,conform,trim,import
+      WORKER_QUEUES: proxy,conform,trim,import,playout-stage
       RUN_PROMOTION: "true"
       PROXY_CONCURRENCY: "2"
+      PLAYOUT_MEDIA_DIR: /media
       NVIDIA_VISIBLE_DEVICES: GPU-79afca3e-2ab2-a6ea-1c44-706c1f0a26d6
       WORKER_LABEL: "zampp1 / Tesla P4"
       NVIDIA_DRIVER_CAPABILITIES: video,compute,utility
     volumes:
       - /mnt/NVME/MAM/wild-dragon-growing:/growing
+      - /mnt/NVME/MAM/wild-dragon-media:/media
     networks:
       - wild-dragon
 
@@ -176,12 +181,22 @@ services:
       - "${PORT_WEB_UI:-7434}:80"
     volumes:
       - /mnt/NVME/MAM/wild-dragon-live:/live
+      - /mnt/NVME/MAM/wild-dragon-media:/media:ro
       - /dev/shm:/dev/shm
       - /run/dbus:/run/dbus
       - /run/systemd:/run/systemd
     networks:
       - wild-dragon
 
+  # Build-only: the CasparCG sidecar image. mam-api spawns these on-demand per
+  # channel (one container per playout channel), so this service is never up'd —
+  # it exists so `docker compose build playout` produces the image the API tags
+  # via PLAYOUT_IMAGE. Profile excludes it from default `up`.
+  playout:
+    profiles: ["build-only"]
+    build: ./services/playout
+    image: wild-dragon-playout:latest
+
 volumes:
   postgres_data:
   redis_data: