[JavaScript] React Router v7 support

[lforst]

Description

React router v7 released which is the next major version of Remix: https://reactrouter.com/upgrading/remix

In theory, we should have all the building blocks to support RR7, we just need to come up with a story on setup and packaging.

[AbhiPrasad]

@petrpacas - we've documented the initial browser-side instrumentation here: https://docs.sentry.io/platforms/javascript/guides/react/features/react-router/v7/

Given react router v7 is replacing remix, we need a solution to also support the server-side setup. That is being tracked by #14519, but that will take longer because we need to create a new package (@sentry/remix -> @sentry/react-router).

[mydea]

Closing this, you can track progress on RR7 (Framework) SDK here: #14519