ocaml: phase 5.1 conformance.sh + scoreboard (283 tests across 14 suites)

lib/ocaml/conformance.sh runs the full test suite, classifies each
result by description prefix into one of 14 suites (tokenize, parser,
eval-core, phase2-refs/loops/function/exn, phase3-adt, phase4-modules,
phase5-hm, phase6-stdlib, let-and, phase1-params, misc), and emits
scoreboard.json + scoreboard.md.

Per the briefing: "Once the scoreboard exists (Phase 5.1), it is your
north star." Real OCaml testsuite vendoring deferred — needs more
stdlib + ADT decls to make .ml files runnable.

lib/ocaml/scoreboard.json

@@ -0,0 +1,21 @@
+{
+  "suites": {
+    "eval-core": {"pass": 47, "fail": 0},
+    "let-and": {"pass": 3, "fail": 0},
+    "misc": {"pass": 39, "fail": 0},
+    "parser": {"pass": 85, "fail": 0},
+    "phase1-params": {"pass": 2, "fail": 0},
+    "phase2-exn": {"pass": 6, "fail": 0},
+    "phase2-function": {"pass": 3, "fail": 0},
+    "phase2-loops": {"pass": 4, "fail": 0},
+    "phase2-refs": {"pass": 6, "fail": 0},
+    "phase3-adt": {"pass": 13, "fail": 0},
+    "phase4-modules": {"pass": 12, "fail": 0},
+    "phase5-hm": {"pass": 17, "fail": 0},
+    "phase6-stdlib": {"pass": 29, "fail": 0},
+    "tokenize": {"pass": 18, "fail": 0}
+  },
+  "total_pass": 284,
+  "total_fail": 0,
+  "total": 284
+}