[Fargate] [request]: active directory joining from windows fargate containers

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**Tell us about your request**
What do you want us to build?
Support for windows fargate to join directory service. Helps apps relying on windows authentication feature.

**Which service(s) is this request for?**
Fargate, ECS

**Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard?**
What outcome are you trying to achieve, ultimately, and why is it hard/impossible to do right now? What is the impact of not having this problem solved? The more details you can provide, the better we'll be able to understand and solve the problem.
We have asp dot net app, currently running in on prem and served by IIS server. IIS is configured to use windows authentication, A native windows login appears when app is accessed which allows us to provide AD service user credentials. This feature is currently lacking with windows containers backed by ECS Fargate.

**Are you currently working around this issue?**
How are you currently solving this problem?
NA

**Additional context**
Anything else we should know?
NA

**Attachments**
If you think you might have additional information that you'd like to include via an attachment, please do - we'll take a look. (Remember to remove any personally-identifiable information.)

No repository files, tests, or implementation entry points are identified in the issue. Start by reviewing the Fargate and ECS Windows-container documentation and the existing roadmap scope for Directory Service integration; done would require documented support for Windows Fargate containers to join a directory and enable the described Windows authentication flow.

Written by the indexing model from the issue text.