Split up the action button methods for monitoring and starting a task

Previously the start task method of action button handled awaiting polling and resetting variables when the task completes. If an ongoing task was found polling was started so that logs could be communicated but no clean up happened when the task finished. This has been split up and the checks for ongoing tasks improved so they also clean up after ongoing tasks finish.

Closes #442 (closed)

This MR contains the following

• Split up start task into the staring of the task, monitoring, and clean up
• Ensure that the monitoring and clean up happen for ongoing task that are detected on mount.

Merge checklist:

• All new/changed functions have up to date typehints and docstrings
• Any UI updates have a before and after screenshot in the MR description No visible changes
• Unit testing of new functionality has similar or better coverage than similar existing code
• This code has been tested on a microscope
  • Webapp has been recompiled, with aesthetic changes checked in light and dark mode (if changed)
  • With updated settings JSON (if changed)
  • SmartScan and live stitching work