Public Branding

Public: branding for a school slug, for the LOGIN and signup screens.

Deliberately separate from /by-slug/{slug}/join, in two ways that matter:

• it never returns an invite code. The join page hands one out on purpose (the school mails that link out); a login screen has no business minting one, so this endpoint carries branding and nothing else.
• it ALWAYS returns 200. A login screen has no school context of its own — the slug arrives as ?school= on the URL the school sent, or is remembered client-side from an earlier /join/<slug> visit, and very often is simply absent. Unknown, inactive and missing all resolve to FluenTea's own branding rather than an error, because the correct answer to "which university is this student from?" when we do not know is ours: showing a student the wrong university's logo is far worse than showing them none.