UI is unusably slow with 100+ cards

[uhppoted]

Ref. https://github.com/uhppoted/uhppoted-httpd/discussions/34#discussioncomment-10423271

With 100+ cards the user interface is sluggish to the point of being unusable:

• [x] Cache element queries
• [x] Loading windmill
• [x] Optimise rollback-all
• [x] Optimised commit-all
• [x] nightly builds
• [x] Optimise grules evaluations
• [x] Incremental/paged load

[twystd]

Baseline performance with 200 cards:

[twystd]

With basic 'query' cache:

[twystd]

With cached query and query modified:

[twystd]

rollback-all:

[twystd]

rollback-all (with caching):

[twystd]

rollback-all (modified only):

[twystd]

With UI optimizations:

Network call is now the bottleneck.

[twystd]

Slow network call is the consequence of evaluating grules for the 1000+ objects that make up the cards list for 200+ cards.

[twystd]

Caching grules CanView evaluations reduces initial network call to 600ms and subsequent calls to 50ms. Initial load time is now below 2s.

[uhppoted]

Implemented prefetch on page load to fetch first page of cards:

[uhppoted]

Initial time to load reduced to ~500ms - closing this as 'good enough for now' and deferring virtual lists to a separate issue (https://github.com/uhppoted/uhppoted-httpd/issues/45).