Manipulating active notifications must be done on the Avalonia UI thread. UpdateNotification and CloseNotification were not properly doing this.
Any plugin attempting to use persistent notifications would have encountered these errors.
NOTE: There is not yet hooks for cleaning up persistent/infinite timeout notifications when the APP is closed.
* WIP: initial commit for observatory herald
* Plugin error handling refactor
* make error window non-modal
* tidy up plugin error handling
* first pass for basic herald functionality
* corrections for linux env
* Use FNV hash directly instead of managing through dictionary/index file
* resolve audio queuing issue, switch to personal NetCoreAudio fork
* merge cleanup
* add enable setting, populate defaults
* framework xml doc update
* Adjust settings, add style selection, replace locale with demonym in dropdown list.
* Test is position is on screen before saving/loading.
* use a default that's actually in the list
