haskell: Phase 8 — print x = putStrLn (show x) in prelude (replaces builtin)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plans/haskell-completeness.md

@@ -102,7 +102,7 @@ No OCaml changes are needed. The view type is fully representable as an SX dict.
   shows with escaped double-quotes). _Deferred:_ `"'a'"` Char single-quotes
   (needs Char tagging — currently Char = Int by representation, ambiguous in
   show); `\n`/`\t` escape inside Strings.
-- [ ] `show` Prelude binding calls `hk-show-val`; `print x = putStrLn (show x)`.
+- [x] `show` Prelude binding calls `hk-show-val`; `print x = putStrLn (show x)`.
 - [ ] `deriving Show` auto-generates proper show for record-style and
   multi-constructor ADTs. Nested application arguments wrapped in parens:
   if `show arg` contains a space, emit `"(" ++ show arg ++ ")"`.
@@ -286,6 +286,14 @@ No OCaml changes are needed. The view type is fully representable as an SX dict.
 
 _Newest first._
 
+**2026-05-06** — Phase 8 `print` is `putStrLn (show x)` in prelude:
+- Added `print x = putStrLn (show x)` to `hk-prelude-src` and removed the
+  standalone `print` builtin. `print` now resolves through the Haskell-level
+  Prelude path; lazy reference resolution handles the forward call to
+  `putStrLn` (registered after the prelude loads). `show` already calls
+  `hk-show-val` from the Phase 8 audit. do-io / program-fib / program-fizzbuzz
+  remain green.
+
 **2026-05-06** — Phase 8 audit: `hk-show-val` matches Haskell 98 format:
 - `eval.sx`: introduced `hk-show-prec v p` with precedence-based parens.
   Top-level `show (Just 3)` = `"Just 3"` (no parens); nested `show (Just (Just 3))`