Configure flexible deployment with environment variables

- Change Flask port from 8080 to 5000 for consistency
- Add environment-based network mode configuration (bridge/host)
- Support both Windows Docker Desktop and Linux LXC deployments
- Remove obsolete docker-compose version and conflicting network settings
- Add .env.example with platform-specific configuration guidance

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/app.py

@@ -197,4 +197,4 @@ def scan_network():
     return jsonify(result)
 
 if __name__ == '__main__':
-    app.run(host='0.0.0.0', port=8080, debug=False)
+    app.run(host='0.0.0.0', port=5000, debug=False)