Database changes:
- Add unique index on saved_filters(user_id, name, resource_type)
Prevents duplicate filter names while allowing same name across
different users or different resource types
Search functionality fix:
- Remove DISTINCT ON (mi.id) from SearchMediaItemsUnified query
- Remove mi.id from ORDER BY clause (was required by DISTINCT ON)
- This allows user-selected sort field to be primary sort criteria
- Previously results were always sorted by ID first, making sort
dropdown ineffective
- Relevance score and title remain as fallback sorts
This fixes the sort dropdown functionality on the bookshelf page
where changing the sort option appeared to have no effect.