feat(JSR): add JSR presence

[LitoMore]

Description

Add the JSR presence for https://jsr.io.

Acknowledgements

• I read the Presence Guidelines
• I linted the code by running yarn format
• The PR title follows the repo's commit conventions

Screenshots

Proof showing the creation/modification is working as expected

[carolinaisslaying]

It looks fine from my perspective, but I'm not that involved with the project, so don't take my word for it. You probably want to have a look at that description though, as I imagine it won't be merged until you correct it to something other than "TODO".