Add ReactNativeSpanFactory class

[yousif-bugsnag]

Goal

Allow platforms to provide their own span factory class that extends the core SpanFactory class in client options.

Adds the outline for a specialised ReactNativeSpanFactory class to support the native integration.

Design

ReactNativeSpanFactory doesn't do anything yet - this PR just puts in place the basic structure for extending the core span factory and will be built upon in subsequent PRs

Testing

Updated some broken unit tests and relied on CI

[github-actions]

Browser bundle size

NPM build

	Package
Before	210.63 kB
After	211.89 kB
±	+1,260 bytes ⚠️

CDN build

	Unminified	Minfied	Minified + gzipped
Before	107.59 kB	40.60 kB	11.89 kB
After	107.84 kB	40.67 kB	11.93 kB
±	+249 bytes ⚠️	+74 bytes ⚠️	+35 bytes ⚠️

Code coverage

Ok	File (✨=New File)	Lines	Branches	Functions	Statements
✅	/home/runner/work/bugsnag-js-performance/bugsnag-js-performance/packages/core/lib/core.ts	100% (+0%)	94.44% (+0.69%)	92.85% (+0%)	98.48% (+0.02%)
🔴	/home/runner/work/bugsnag-js-performance/bugsnag-js-performance/packages/platforms/react-native/lib/index.ts	0% (+0%)	0% (-100%)	0% (+0%)	0% (+0%)
🔴	✨ /home/runner/work/bugsnag-js-performance/bugsnag-js-performance/packages/platforms/react-native/lib/span-factory.ts	66.66% (+66.66%)	100% (+100%)	50% (+50%)	83.33% (+83.33%)

Total:

Lines	Branches	Functions	Statements
90.14%(-0.07%)	80.14%(-0.54%)	87.77%(-0.12%)	88.91%(-0.05%)

Generated against 591174c on 18 December 2024 at 17:35:20 UTC

[gingerbenw]

I'm sure we could update the configure method here so the second parameter can be ReactNativeSpanFactory but totally happy for that to come later