New lines can be an important part of a user's prompt and trimming
it can alter the results. We previously only trimmed prompts with
images but refactoring brought this behavior to all prompts, where
it became more noticable.
The /generate endpoint adds less whitespace and therefore doesn't
need to trim it out - this brings the same behavior to /chat.
Thanks to @gabe-l-hart for spotting the issue!
Fixes#7795
900f64e6be