test: physical health and stricter parity in timing harness

Untimed physical-leaf/fluid health after warm-up and after each timed
window using the existing runner limits (finite macros, rho in [0.5,1.5],
max Mach <= 0.2); refined masks as in run_refined_dfg. Parity comparator
rejects unequal level counts and any infinity; matching NaN stays allowed
only as a storage mask. Regression tests for both. No numerical gate or
production change.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/unit/test_time_refined_dfg.py

@@ -42,6 +42,21 @@ class TimingHarnessContract(unittest.TestCase):
         self.assertIn("bits", t.same_state([a], [b]))
         c = a.copy(); c[0, 0] = np.nan
         self.assertIn("NaN", t.same_state([a], [c]))
+        self.assertIn("level count", t.same_state([a], [a, a]))
+        inf = a.copy(); inf[1, 0] = np.inf
+        self.assertIn("infinite", t.same_state([inf], [inf.copy()]))  # matching inf still fails
+        self.assertIn("infinite", t.same_state([a], [inf]))
+
+    def test_physical_health_limits(self):
+        ok = (np.array([1., 1.01]), np.array([.01, .02]), np.array([0., .01]))
+        health = t.physical_health([ok])
+        self.assertAlmostEqual(health["rho_max"], 1.01)
+        for bad in ((np.array([1., np.nan]),) + ok[1:],
+                    (np.array([.4, 1.]),) + ok[1:],
+                    (ok[0], np.array([.2, 0.]), ok[2]),
+                    (np.array([]), np.array([]), np.array([]))):
+            with self.assertRaises(RuntimeError):
+                t.physical_health([bad])
 
     def test_summary_reports_differences_without_claims(self):
         rows = [dict(variant=v, seconds=s) for v, s in