Smooth Flutter Web Scrolling

Issue description: https://stackoverflow.com/questions/79857842/scroll-is-janky-while-items-are-not-rebuilding?noredirect=1#comment140923421_79857842

Source code: https://github.com/polina-c/tf (the repo is private, so give me your github name to be added as contributor)

Acceptance criteria:
• Pull request with nice clear code change, that makes scroll for home page not janky, without introducing regressions
• A short summary explaining the root cause

Please, open http://the-field.world on IPhone Chrome and check you see the issue before bidding.