Allow doc additions to DPG-generated methods

[heaths]

For protocol methods like in PR #29144, we'd like to document that clients should always set the stringIndexType property to "Utf16CodePoint" for .NET strings. We can do this with models, but if they don't do it for .NET the string offset and length may not come back correctly.

It would be great if we could somehow add a <remarks> section, which the generator doesn't generate now (just summary, param, and exception sections). Off hand, I don't have any ideas. At worst, maybe an x-ms-remarks extension for autorest.csharp?

Even when we have models and default this for .NET - either with x-ms-client-default or like we did for the Question Answering HLC SDK - this would still be important for the protocol methods.

[pallavit]

@heaths do you still see value is doing this?

/cc: @lirenhe for triaging as appropriate.

[heaths]

Yes, and I think we need a TypeSpec way to do this as well, though maybe client TSPs can accomplish that. @m-nash? For context, basically I want to be able - through client customizations or something - "attach" language-specific (or even generic, non-REST) docs without having to override the method just to add my own documentation.

[github-actions]

Hi @heaths, we deeply appreciate your input into this project. Regrettably, this issue has remained unresolved for over 2 years and inactive for 30 days, leading us to the decision to close it. We've implemented this policy to maintain the relevance of our issue queue and facilitate easier navigation for new contributors. If you still believe this topic requires attention, please feel free to create a new issue, referencing this one. Thank you for your understanding and ongoing support.