docs: Add XML doc comments to resolve missing-documentation warnings - #17

The field 'StilVueServiceClientBuilder._areaAffixUrl' is assigned but its value is never used

Possible null reference argument for parameter 'failMessage' in 'void IProtectedAsMock<HttpClientHandler, IHttpMessageHandler>.Verify<TResult>(Expression<Func<IHttpMessageHandler, TResult>> expression, Times? times = null, string failMessage = null)'.

Possible null reference return.

Converting null literal or possible null value to non-nullable type.

Converting null literal or possible null value to non-nullable type.

Possible null reference return.

Converting null literal or possible null value to non-nullable type.

Object or collection initializer implicitly dereferences possibly null member 'SignedXml.SignedInfo'.

Dereference of a possibly null reference.

Dereference of a possibly null reference.

Dereference of a possibly null reference.

Dereference of a possibly null reference.

Possible null reference return.

Possible null reference return.

Nullability of type of parameter 'document' doesn't match overridden member (possibly because of nullability attributes).