Performance improvements in loading Alerts

[Enigmatrix]

Alerts page, Add Alert, Edit Alert are all slightly slow, the worst being the Alerts page. Improve performance by figuring out what's taking so long in the first place.

• [ ] Use MiniProfile on our EF Core queries.
• [ ] Write more timing measurements using ILogger, see file for timing. I assume Debug window is not showing true times.
• [x] Try to synchronously pre-load items into memory from Home/Experiments page, then just constructor-assign them to the view model to check if it's just Avalonia being slow.

[Enigmatrix]

De-prioritizing this as this doesn't seem like a easily solved issue. Plus it seems like EntityFramework initialization might be a cause. For example, refreshing the Alerts page by navigating elsewhere and coming back makes the query one-tenth of the time, so it could be just EF or it could be Avalonia navigation or Avalonia page initialization async.