feat: add a script to watch for drops (#1671)

# Description

This PR introduces a comprehensive script, designed to monitor network
packet drop counters in Kubernetes clusters. It automates the detection
of either Retina or Cilium network monitoring agents, retrieves relevant
metrics, and presents a clear, actionable summary of changes over time.

## Usage
<node_name>: The name of the Kubernetes node to monitor.
[interval]: The polling interval in seconds (default: 30).
--debug: Enables debug output.

## Technical Details
Agent Detection: Uses kubectl to identify Retina or Cilium pods based on
labels.
Metrics Retrieval: Employs curl to fetch metrics from agent and Hubble
endpoints.
Change Analysis: Compares metrics using associative arrays and awk for
numeric calculations.
Port Forwarding: Leverages kubectl port-forward to access metrics
endpoints.

## Dependencies
kubectl
curl
grep
sort
lsof (optional)

<img width="788" alt="image"
src="https://github.com/user-attachments/assets/476b9b3a-4d55-4984-90a7-26322de87c6a"
/>

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Signed-off-by: Vamsi Kalapala <vakr@microsoft.com>

Author: Vamsi Kalapala