chore: use env-var port bindings — no hardcoded host ports

All host ports are now configurable via .env variables with sensible
defaults. This prevents collisions when deploying alongside existing
services on TrueNAS or any other host.

docker-compose.yml

@@ -31,7 +31,7 @@ services:
       queue:
         condition: service_started
     ports:
-      - "7432:3000"
+      - "${PORT_MAM_API:-7432}:3000"
     volumes:
       - /var/run/docker.sock:/var/run/docker.sock
     environment:
@@ -53,9 +53,9 @@ services:
     depends_on:
       - mam-api
     ports:
-      - "7433:3001"
-      - "1935:1935"       # RTMP ingest (listener mode)
-      - "9000:9000/udp"   # SRT ingest (listener mode)
+      - "${PORT_CAPTURE:-7433}:3001"
+      - "${PORT_RTMP:-1935}:1935"         # RTMP ingest (listener mode)
+      - "${PORT_SRT:-9000}:9000/udp"      # SRT ingest (listener mode)
     privileged: true
     environment:
       S3_ENDPOINT: ${S3_ENDPOINT}
@@ -86,7 +86,7 @@ services:
   web-ui:
     build: ./services/web-ui
     ports:
-      - "7434:80"
+      - "${PORT_WEB_UI:-7434}:80"
     networks:
       - wild-dragon