chore: connect bot container to proxy_net for nginx reverse-proxy

This allows nginx-edge to reach the bot via service name
on the shared proxy_net external network.

docker-compose.yml

@@ -10,10 +10,16 @@ services:
     environment:
       - BOT_TOKEN=${BOT_TOKEN}
       - HTTP_PROXY=${HTTP_PROXY-}
+      - HTTPS_PROXY=${HTTPS_PROXY-}
       - DB_PATH=/data/db.sqlite3
     volumes:
       - worktime_data:/data
 
+networks:
+  default:
+    name: proxy_net
+    external: true
+
 volumes:
   worktime_data:
     driver: local