Export noops from browser package when window or document is undefined

[yousif-bugsnag]

Goal

Prevent the SDK from crashing when used in SSR frameworks such as Next or Nuxt.

Currently window and document are accessed when the library is imported which causes a crash when the code is executed server-side as these are not defined.

This PR aims to prevent this and allow the SDK to be used in SSR apps, by exporting a noop client, onSettle and routing provider if window and document are undefined.

Testing

Added unit tests for the onSettle and routing provider noops, and tested manually with a Next.js app

[github-actions[bot]]

Browser bundle size

NPM build

	Package
Before	175.95 kB
After	177.45 kB
±	+1,497 bytes ⚠️

CDN build

	Unminified	Minfied	Minified + gzipped
Before	84.94 kB	31.99 kB	9.84 kB
After	85.98 kB	32.33 kB	9.93 kB
±	+1,039 bytes ⚠️	+335 bytes ⚠️	+91 bytes ⚠️

Code coverage

Ok	File (✨=New File)	Lines	Branches	Functions	Statements
🔴	/home/runner/work/bugsnag-js-performance/bugsnag-js-performance/packages/platforms/browser/lib/browser.ts	87.5% (-8.92%)	75% (-25%)	50% (+0%)	87.5% (-8.92%)
🔴	/home/runner/work/bugsnag-js-performance/bugsnag-js-performance/packages/platforms/browser/lib/default-routing-provider.ts	100% (+0%)	60% (-15%)	100% (+0%)	100% (+0%)

Total:

Lines	Branches	Functions	Statements
92.06%(-0.15%)	80.9%(-0.2%)	93.98%(+0.09%)	90.13%(-0.11%)

Generated against d18dca8edb8e208dbbca83648bef93afe7bafc0d on 2 January 2024 at 10:29:11 UTC