docs & small optimizations to dom ops

[richrobber2]

i added some js docs and made some dom optimizations such as:

• switching to using Object.assign for some variable assignments to avoid multiple dom calls
• using guard clauses
• used optional chaining operator to avoid errors
• and more but you gotta look over the code changes for more

[richrobber2]

any more speed ups would have to come from the .svlte file for the gradio component

[daswer123]

Cool, the documentation will definitely help others understand what's even going on in the code :) And general improvement of the code is also good.

I'll go through the code now, test it on different versions and I think it will be ready to merge :)

[daswer123]

In general checked on all versions from March 25 to version 1.5, everything works, no errors noticed. I think we can do a merge, a little more testing and that's it :)

[richrobber2]

yes, do note that i didnt do a ton of testing

[daswer123]

Checked all versions again, everything works.