Module poller 

Provides functionality for polling AWS CloudWatch Logs using the FilterLogEvents API.

This module is responsible for:

• Spawning an asynchronous task that periodically polls a set of log group ARNs.
• Managing timestamps for each log group to fetch only new events since the last poll.
• Handling pagination for FilterLogEvents responses.
• Processing log event messages from the polled data using functions from the processing module.
• Sending the resulting TelemetryData (or errors) over an MPSC channel to the main application logic.

Functions

start_polling_task

Spawns a task that polls FilterLogEvents for multiple log groups and sends results over a channel.