Make the client library separate for much smaller install

[natew]

One.js is now shipping React scan, but it massively increases or npm install size. And since we use it for both our runtime and as our CLI install (npx one) it slows down getting started a lot too.

This is because there’s a bunch of backend type dops included like playwright.

Creating a new “@react-scan/client” library would greatly help this. Would love to see this, or we may need to split it out into a separate plugin until then. I can maybe help a bit with the initial split if you are strapped for time.

[RobPruzan]

This is a priority for us in the next release