Drop dead-regime distributed=False workaround on assets grid.

The pylcm sharding-consistency validator now requires every state to
carry the same `distributed` flag in every regime that declares it.
Restoring `assets` to the shared grid lets the dead regime's V-array
sharding match the alive regimes that transition into it.

Also drops the test that codified the workaround.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: hmgaudecker

src/aca_model/baseline/regimes/_common.py

@@ -449,7 +449,7 @@ def build_dead_regime(grids: Grids) -> Regime:
             "utility_scale_factor": preferences.utility_scale_factor,
         },
         states={
-            "assets": grids.assets.replace(distributed=False),
+            "assets": grids.assets,
             "pref_type": grids.pref_type,
         },
         active=lambda _age: True,

tests/test_model_creation.py

@@ -58,18 +58,6 @@ def test_dead_regime_is_terminal() -> None:
     assert model.user_regimes["dead"].terminal
 
 
-def test_dead_regime_assets_grid_not_distributed() -> None:
-    """The terminal `dead` regime declares its `assets` grid non-distributed.
-
-    `dead` carries only a tiny `[pref_type, assets]` value function;
-    sharding its assets axis across devices buys nothing and makes its
-    V-array sharding disagree with what the multi-GPU solve produces for
-    the regimes that transition into it.
-    """
-    dead = build_regime("dead")
-    assert dead.states["assets"].distributed is False
-
-
 def test_non_terminal_regimes_not_terminal() -> None:
     model = make_baseline_model(n_subjects=1)
     for name in REGIME_SPECS: