fix: gitignore macOS file systems and scoped client serializer extension

[maurei]

• Closes AddClientSerialization should register (de)serializers as scoped services #783
• Also adds macOS system files (.DS_STORE) to gitignore

[bart-degreed]

Looks good to me. Alternatively, we can register IResourceFactory as a singleton as well.

[maurei]

@bart-degreed I think I would prefer that. However, DefaultResourceFactory depends on IServiceProvider, which currently is a scoped service provided because IResourceFactory is scoped. Registering it as a singleton will result in IServiceProvider being the root service provider, from which no scoped services can directly be resolved. This might cause problems right here, what do you think?

[bart-degreed]

Good point, that is going to cause problems indeed. Because what typically will be injected as a resource parameter is DbContext, which is scoped. Sounds like we'll need to make them all scoped then, which is what you initially proposed.