feat: add environment variable support and update README instructions

docker-compose.yml

@@ -21,6 +21,10 @@ services:
     image: telegraf:1.33.1
     volumes:
       - ./telegraf.conf:/etc/telegraf/telegraf.conf:ro
+    environment:
+      - DATABASE=${TELEGRAF_MONGODB_DATABASE:?"Database name is required"}
+      - DSN=${TELEGRAF_MONGODB_DSN:?"DSN is required"}
+      - HOSTNAME=${TELEGRAF_HOSTNAME:?"Hostname is required"}
     networks:
       - backend
 
@@ -34,6 +38,8 @@ services:
         condition: service_healthy
       telegraf:
         condition: service_started
+    environment:
+      - VIDEO_URL=${VIDEO_URL:?"Video URL is required"}
     networks:
       - backend