Coalesce makes an attempt to read some events from `eventChan` so that multiple file changes that happen at the same time from the user's perspective are grouped together.

BufferMaxDuration prevents excessive delays when bundling together file changes by emitting an event to the channel if the threshold is reached even if new file changes are still coming in.

BufferMinRestDuration bundles many file changes together by waiting a short amount of time after a file change before emitting an event to the channel.