Function launcher_not_found 

pub fn launcher_not_found(id: &str) -> Response

404 body for a launcher id that doesn’t resolve to any palette-exposed tool. The lookup happens in this crate, before any call reaches SomaApplication, so there is no real ApplicationError to map — but the body is still built as an ApplicationError value (rather than a hand-rolled json! literal) so every /v1/palette/* error response, found-then-failed or never-found, shares one wire shape (code/message/retryable/remediation/details) for the frontend.