Advanced sorting

[mm12]

I would love to see things like sorting by fields (broadly) on the roadmap. However, this comes with a few issues. Off the top of my head:

1. There are many fields, we will clutter the existing dropdown
2. We can only sort by one field. If a user wanted to sort by the order of a series they were reading, they would need a field like part_number.path or something formatted in a similar way. Additionally, if this is a text-based field (as opposed to what is outlined in [Feature Request]: Numeric field types #1141), they would need leading zeros where applicable.

To solve the 2nd issue, we would need a more advanced sorting system. For example, having a primary and secondary sort. However, the typical way to implement this would not scale (for instance, if we add on volume and such). I think a good way to solve this would be to move sorting into the searchbar. This removed all clutter from item 1, even if we have multiple levels of sorting. As for how we implement these levels, we have several options:

1. Order in the search: not recommended. This means we duplicate special keys regarding sorting, need to count where we are, and the user needs to ensure they don't mix up where their sort term is.
2. Specify order: Probably a better idea. There are several ways to go about this, though. Something like sort:[sorta, sortb] isn't user-friendly, but something like sort0:sorta sort1:sortb is even worse.