[FIX] fool harness: record mlx version correctly + self-hash; trial-03 pre-run addendum

Two instrument defects, both of the class the harness was built to prevent —
a probe that could not look reporting a value that reads like a result:

- environment() read mlx.__version__, which does not exist (only
  mlx.core.__version__). Every run record would have said mlx_version
  "unknown" for an installed, versioned package, losing the one field that
  makes trial 03 comparable to trial 02. It is MLX 0.31.2, identical.
- git_revision() returns null whenever the harness runs outside its repo,
  which is always — it must run on the machine holding the model. The prompt
  and input were hashed; the instrument itself was not. Now self-hashed.

The pre-registration addendum is committed BEFORE the run produced output, so
the ordering is checkable rather than asserted. It records: the 'unruled'
premise expiring at REVIEWED-86 (12:13, 32 min after the pre-registration was
written) and why the ordering favours the ground truth; the contamination that
CANNOT be removed, since the amended doctrine is in the executor's auto-loaded
context and I am therefore not a blind grader; the (a)/anti-echo collision
resolved against my own convenience before output existed; and the seed.

Ground truth (a)-(e) is unrevised and will not be revised.

claude/governance/fool/run_trial.py

@@ -75,31 +75,62 @@ def read_text(path: Path) -> str:
     return path.read_text(encoding="utf-8")
 
 
+def _package_version(dist_name: str, module_name: str, attr_module: str | None = None) -> str:
+    """
+    Resolve a package version without depending on a top-level __version__.
+
+    `mlx` has no `mlx.__version__` — only `mlx.core.__version__` — so the naive
+    getattr fallback silently records "unknown" for an installed, versioned
+    package. That is the exact confusion this harness exists to prevent: a probe
+    that could not look, reporting a value that reads like a result. Installed
+    metadata is asked first; the module attribute is the fallback; and a genuine
+    absence is reported as absence, distinguishably.
+    """
+    try:
+        import importlib.metadata as md
+
+        return md.version(dist_name)
+    except Exception:
+        pass
+    try:
+        import importlib
+
+        mod = importlib.import_module(attr_module or module_name)
+        v = getattr(mod, "__version__", None)
+        if v:
+            return str(v)
+        return "INSTALLED, VERSION UNDETERMINED"
+    except Exception as exc:  # pragma: no cover - environment probe
+        return f"UNAVAILABLE ({exc.__class__.__name__})"
+
+
 def environment() -> dict:
     """Capture enough of the machine to make a later re-run comparable."""
-    env = {
+    return {
         "host": socket.gethostname(),
         "user": getpass.getuser(),
         "platform": platform.platform(),
         "machine": platform.machine(),
         "python": sys.version.split()[0],
-        "mlx_version": None,
-        "mlx_lm_version": None,
+        "mlx_version": _package_version("mlx", "mlx", attr_module="mlx.core"),
+        "mlx_lm_version": _package_version("mlx-lm", "mlx_lm"),
     }
-    try:
-        import mlx.core  # noqa: F401
-        import mlx
 
-        env["mlx_version"] = getattr(mlx, "__version__", "unknown")
-    except Exception as exc:  # pragma: no cover - environment probe
-        env["mlx_version"] = f"UNAVAILABLE ({exc.__class__.__name__})"
-    try:
-        import mlx_lm
 
-        env["mlx_lm_version"] = getattr(mlx_lm, "__version__", "unknown")
+def harness_sha256() -> str:
+    """
+    Hash this file into every run record.
+
+    `git_revision()` returns None whenever the harness is executed outside its
+    repository — which is the normal case, because it must run on the machine
+    holding the model. A run record whose harness field is null cannot be traced
+    to the code that produced it. The prompt and input are already hashed; the
+    instrument itself was not.
+    """
+    try:
+        return sha256(Path(__file__).resolve().read_text(encoding="utf-8"))
     except Exception as exc:  # pragma: no cover
-        env["mlx_lm_version"] = f"UNAVAILABLE ({exc.__class__.__name__})"
-    return env
+        return f"UNAVAILABLE ({exc.__class__.__name__})"
 
 
 def git_revision() -> str | None:
@@ -282,6 +313,7 @@ def main() -> None:
         },
         "environment": environment(),
         "harness_git_rev": git_revision(),
+        "harness_sha256": harness_sha256(),
     }
 
     (RUNS_DIR / f"{slug}.json").write_text(