Fixes T8911. This corrects several issues which could crop up if a calendar event query matched more results than the query limit:
- The desired order was not applied by the SearchEngine -- it applies the first builtin order instead. Provide a proper builtin order.
- When we generate ghosts, we can't do limiting in the database because we may select and then immediately discard a large number of parent events which are outside of the query range.
- For now, just don't limit results to get the behavior correct.
- This may need to be refined eventually to improve performance.
- When trimming events, we could trim parents and fail to generate ghosts from them. Separate parent events out first.
- Try to simplify some logic.