Say in plan.org that write-stdout is all that is under print

plan.org

@@ -380,8 +380,8 @@ wasm32 target cheap, because a primitive is the only thing implemented twice.
 | ~addr~                 | address of a place |
 | arithmetic, comparison, casts | per machine type |
 
-Printing is *not* a primitive. ~print-str~, ~print-f64~ and friends are Flan
-functions over ~write-stdout~. ~println~ and ~print~ are compiler-provided: the
+Printing is *not* a primitive: ~write-stdout~ is the one output primitive and
+~println~ and ~print~ are written over it. Both are compiler-provided — the
 checker walks the concrete type at the call site and emits the printer for it
 (lib/render.ml, shared with the REPL's ~C-x C-e~). This is intentionally not
 user-defined overload resolution — ordinary values remain untagged, and there