WASM/yew performance VERY bad

[sumeet]

this is easy to see when there are a lot of objects on the screen. happens when the easy way to repro is when the ValueRenderer renders a deeply nested JSON response, everything slows down to a crawl.

talked with yew developers, and we should try the following steps to improve things:

• finish converting all UiToolkit draw_* functions to build components instead of rendering HTML directly. yew is faster at comparing components which know if they need to rerender, rather than diffing their generated HTML.
• probably as follow-up, the callback->mutation structure may need to be revisited. Components will contain callbacks that "do the action", like for example a Button component would contain what to do when the button is clicked. there's no good way of comparing these callbacks.

options:

• Do we refactor the application to make these not be callbacks? (rather declarative data-packages containing request information about the mutation that needs to be done)
• or does that not end up mattering really? maybe we just treat all callbacks as "equal" (i.e., don't compare them when comparing the component)