Add detection/mitigation for invalid Windows startup app configuration

We keep getting reports of EarTrumpet startup issues, stemming from what appears to be OS bugs in appmodel/startup task configuration. (This OS feature was refactored and was associated with at least 1 OS bug back in May 2020. It was reportedly fixed at the time.)

To head off repeat reports, we should make an attempt to at least detect known bad configurations and alert the user (e.g., https://github.com/File-New-Project/EarTrumpet/issues/417#issuecomment-566869108). We can utilize similar infrastructure put in place to handle a font OS bug.

Related: https://github.com/File-New-Project/EarTrumpet/issues/417 https://github.com/File-New-Project/EarTrumpet/issues/941 https://github.com/File-New-Project/EarTrumpet/issues/1353 https://github.com/File-New-Project/EarTrumpet/issues/1432