Add API docs for /v1/info

[kurokobo]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

Yes, there is an endpoint /v1/info which can be used to gather app name and its description (and tags by #11242), but this endpoint is not documented at all.
This should be explicitly documented, as it misleads users into misunderstanding that the name of the app, etc., cannot be obtained from the API.

2. Additional context or comments

No response

3. Can you help us with this feature?

• I am interested in contributing to this feature.