[FEATURE]: Expose question "ask" channel for SDK/plugins to use

[eXamadeus]

Feature hasn't been suggested before.

• [x] I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

As originally discussed in #6330 there was a desire to build a way for plugins and clients to "ask" questions. The request QuestionTool implemented that functionality in core and exposed most of the endpoints necessary for this system to work.

One significant endpoint that was not exposed was the /question/ask endpoint. The request is simple:

• Expose the Question.ask functionality via the server

This will allow both SDK users and plugin developers to use the new ask tool.

[!NOTE] This exposes the question.ask functionality for the SDK and API but the plugin is still stuck on v1 of the SDK. I have another PR to upgrade the plugin system to provide a v2 SDK client here: https://github.com/anomalyco/opencode/pull/8380