refactoring: polished some files, .env.example update

docker-compose.yml

@@ -1,5 +1,6 @@
 services:
   postgres:
+    env_file: prod.env
     image: postgres:16-alpine
     container_name: maleniabot_db
     environment:
@@ -20,6 +21,7 @@ services:
       retries: 5
 
   bot:
+    env_file: prod.env
     build:
       dockerfile: Dockerfile
     container_name: maleniabot_bot