Support Zotero tags

[ailintom]

Support Zotero tags

[plandes]

@ailintom Cool idea! Regarding the changes to the client side tree: for things like this it should only require adding to the tree as it is as it was designed to be annotated with additional metadata.

However, filtering (at least in my collection) by keyword in the tree (search box top left) is already painfully slow. Filtering by tag would require set operations across the entire collection for every paper in every collection. For this reason, I really doubt it would be performant to do this in the client.

However, filtering on the site creation side would be more feasible given an SQL join with tags more tractable (assuming these columns are indexed).

Another way to do this on the client side is to add flask and dynamically generate the tree and reload. This would solve the string search that's already there and this as well. However, that would be an even larger set of changes.