This PR removes all mentions of "(optional)" from our jsdocs. This is
for:
* consistency — many of our jsdocs don't mention "(optional)" for
optional parameters. The developer is expected to use the type
definition to find this out. But it's a bit unclear because we use
"(optional)" in many places too.
* docs site — on our docs site, we use type definitions to figure out
what is optional, and what isn't. We use that info to denote optional
parameters. It looks funny having two "(optional)"s on a page. We
*could* strip them, but it's probably better to just remove them at the
source.
<img width="526" alt="image"
src="https://github.com/tldraw/tldraw/assets/15892272/b5b65a2b-2923-42a9-a2d3-9b1d9d55cd3d">
### Change Type
- [x] `documentation` — Changes to the documentation only[^2]
### Release Notes
- dev: Removed duplicate/inconsistent `(optional)`s from docs
828848f8af