PLAT-6370 unity support

[kstenerud]

Goal

Expose BSGBreadcrumbTypeValue and BSGBreadcrumbTypeFromString via BugsnagBreadcrumb+Private.h

This is needed to support bugsnag/bugsnag-unity#234

Testing

Re-run unit and e2e tests

[github-actions]

Infer: No issues found 🎉

OCLint: No issues found 🎉

Bugsnag.framework binary size did not change - 1,125,144 bytes

Generated by 🚫 Danger

[nickdowell]

This has introduced a lint warning, and I'm not sure that the introduction of an "unknown" string is desirable.

Maybe the Unity layer could deal with the NSDictionary representation which can be accessed via -[BugsnagBreadcrumb objectValue] ?

[kstenerud]

I'd rather avoid using dictionary lookups to get internal values and instead make use of the type checker and type bindings. Otherwise we have to manually keep everything in sync across multiple projects, and that's asking for trouble.

[nickdowell]

We could use the FOUNDATION_EXPORT macro to take care of the extern "C" dance thereby tidying up the code a bit:

Suggested change

	#ifdef __cplusplus
	extern "C" {
	#endif
	NSString *BSGBreadcrumbTypeValue(BSGBreadcrumbType type);
	BSGBreadcrumbType BSGBreadcrumbTypeFromString( NSString * _Nullable value);
	#ifdef __cplusplus
	}
	#endif
	FOUNDATION_EXPORT NSString *BSGBreadcrumbTypeValue(BSGBreadcrumbType type);
	FOUNDATION_EXPORT BSGBreadcrumbType BSGBreadcrumbTypeFromString(NSString * _Nullable value);