Handle EmptyContent

[HugoBurgess]

PR Classification

Code cleanup to improve robustness and compatibility across .NET versions.

PR Summary

Introduced a new method HasContent to handle HttpResponseMessage.Content checks more reliably.

• Result class: Added HasContent method to check if HttpResponseMessage.Content is not null and not EmptyContent.
• Updated WithStreamData, WithObjectData, and CreateResultAsync methods to use HasContent for content checks.
• Removed unnecessary whitespace changes in ReadAsTypeAsync and ReadAsStreamAsync methods.

[JiviteshT]

Looks good