fix: update `README.md` to correct `npx` command

[baseballyama]

now npx analyze-trace returns 404 error. We need @typescript/ prefix.

npm error code E404
npm error 404 Not Found - GET https://registry.npmjs.org/analyze-trace - Not found
npm error 404
npm error 404  'analyze-trace@*' is not in this registry.
npm error 404
npm error 404 Note that you can also install from a
npm error 404 tarball, folder, http url, or git url.

[jakebailey]

The first thing https://github.com/microsoft/typescript-analyze-trace?tab=readme-ov-file#usage does is ask you to install the package locally, which makes the instructions work; there are also two other commands this package provides that would be unavailable when using npx without the local install.

[baseballyama]

I misread this because there are very few cases where both npm install and npx are needed. Thank you!