Document Smart Date Recur's differences from Date Recur module

On save Smart Date converts the instances in any recurring events into separate field deltas, so they can be easily accessed and displayed using views, etc. As such, the multivalue processor introduced to Search API Solr in ✨ Add a unique values processor for multi-valued fields Fixed should work with Smart Date's recurring dates.

As for other design decisions to take into account... Smart Date provides a host of other improvements for managing dates and times in Drupal, including:
- An intuitive and easy to use widget
- Intelligent formatting of date ranges
- Support for timezone handling
- The ability to set granularity for views filters
- Integration with multiple calendar solutions, including drag-and-drop editing in Fullcalendar View
- Integration with other popular Drupal ecosystems like the Migrate API, Serialization/HAL/Default Content, and Feeds
- A system of Date Augmenters → that provide additional capabilities for formatting and using dates and times

Thank you!

What Date Recur Search API is doing is creating a new index so that it can make copies of a piece of content for every recurring date. I don't know yet if Date Recur puts each occurrence into a separate delta like Smart Date Recur (at first look i thought it did), but the key part with Search API integration is that each of the dates (lets say multiple values in a multiple value field) produces a new item in the search index. So an event with ten dates gets added to the index ten times, once for each date.

If Date Recur does multivalue like Smart Date Recur it will i hope be trivial to modify Date Recur Search API, and then the question is should that be a bundled submodule of Smart Date or live on its own. But if there is another way to be able to see the same node multiple times for each datetime in a Search API listing, so that exposed sorts and exposed filters work as expected … well i probably should open / look for a feature request for that.