Performance: skip jsdoc parsing in various places
#2170May result in microscopic wins, every milisecond counts: microsoft/TypeScript#55739 Can use this in svelte2tsx, maybe other locations, too. Usable in TS 5.3+
Checked this, not sure if we can leverage this:
$props()
, we may be able to omit this if we're checking if this is a JS file or not