research: VIV driver — fail closed on any non-finite recorded output

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

tests/unit/test_viv_logic.py

@@ -86,3 +86,11 @@ def test_viv_config_passes_the_real_loader(tmp_path):
     assert (cfg.nx, cfg.ny) == (nx, ny) == (3000, 2400)
     assert cfg.collision == "MRT" and cfg.y_wall_bc == "free_slip" and cfg.velocity == .04
     assert math.isclose(cfg.viscosity, .04 * 40 / 150)
+
+
+def test_finite_rejects_any_nonfinite_recorded_output():
+    row = (3, .1, .2, .3, .4, .5, .6, .7, 0.0)
+    assert viv.finite(row)
+    for i in range(len(row)):
+        for bad in (float("nan"), float("inf"), -float("inf")):
+            assert not viv.finite(row[:i] + (bad,) + row[i + 1:])