All 10 vector primitives now have :as type annotations on every parameter,
:returns types, and :doc strings. make-vector gains optional fill annotation;
vector uses :rest for its variadic args; vector-ref/set! document bounds error.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
vector-ref and vector-set! now raise Eval_error on out-of-bounds index instead of
an OCaml array exception. vector-copy accepts optional start and end parameters for
slicing (R7RS §6.8). spec/primitives.sx doc updated to reflect slice params.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>