Set response body

[humanizersequel]

Problem

In the HTTP server, results are serialized into a format such that any HTTP response is wrapped in a {ok : {actual content}} format. So if any external thing is sensitive to the format of the response's body, it will fail outright because it doesn't handle that when decomposing the body JSON.

Solution

Introduces a check before sending off a final_body HTTP response for an optional manual override that replaces the usual Result serialization with some declared raw body value, as well as a Hyperapp function to invoke it. This change should be completely backwards compatible since if there is no raw body value declared it passes through the serialized result as usual.

Docs Update

lmfao

Notes

This PR was written entirely by Claude Sonnet 4.5 (with vigorous guidance from me, but still)