Trivial wrapper: apl-run-file = apl-run ∘ file-read, where
file-read is built-in to OCaml SX.
Tests verify primes.apl, life.apl, quicksort.apl all parse
end-to-end (their last form is a :dfn AST). Source-then-call
test confirms the loaded file's defined fn is callable, even
when the algorithm itself can't fully execute (primes' inline
⍵ rebinding still missing — :glyph-token, not :name-token).