Function admit_inline 

pub fn admit_inline(
    iri_hash: u64,
) -> Option<Result<&'static FunctionEntry, QispError>>

Admission check for an inline expression (FILTER/BIND) use of a QISP function identified by iri_hash:

• Ok(entry) if it is registered and legal inline (deterministic, synchronous, scalar-producing);
• Err(NonDeterministicDisallowed) if registered but async/table-producing (e.g. knn) — it must be invoked as a job / graph operator instead;
• Ok-with-None-semantics is not used: an unregistered IRI returns None so the evaluator can emit a standard unknown-function error.

This lets the evaluator reject an ill-typed inline call before dispatch.