feat: add new response type StreamTraversableResponse

[Altahrim]

Introduced by nextcloud/server#57165

[nickvergessen]

Could add a sample into tests/ to see it works?

[provokateurin]

LGTM, please add a test @Altahrim

[nickvergessen]

Added a line so the new method is tested, but it is failing

[provokateurin]

The output looks wrong, there is no 200 response.

[SebastianKrupinski]

I fixed the errors and re-based. All checks now pass

Outdated

[SebastianKrupinski]

The output looks wrong, there is no 200 response.

What's "missing" is just the response body (no content/schema under 200). That's correct, not a bug: StreamTraversableResponse has no type template in the real OCP class (only status + headers), so the extractor has no schema to emit — same as StreamGeneratorResponse, which is defined identically in ResponseType.php:130-137 (content type null, type null). A streamed/traversable response can yield arbitrary content, so there's no fixed schema to describe.