Switch UI to pagination-based projects and users API

#3489 implemented cursor-based pagination API for /api/project/list and /api/users/list. The UI should switch to the new API for performance.

All the UI functionality is supported via the new API (displaying total count, filtering by name, etc). The only UI change is it won't longer be possible to open a specific page – it'll be prev/next navigation as it's usually done with cursor-based pagination.