<!-- This is an auto-generated comment: release notes by coderabbit.ai -->

## Summary by CodeRabbit

## New Features
* Added `--router` command-line option to filter NetFlow database results by specific router

## Improvements
* Enhanced command-line argument parsing to support optional parameters for increased flexibility
* Optimized data filtering mechanisms to improve query composition and consistency

<!-- end of auto-generated comment: release notes by coderabbit.ai -->