Return equilibrium volume and energy from EOS task (#29)

* refactor eos into task

* task name and cache

* avoid duplicate test on PR branches

* more returned data in eos

* return b1

* minor md test change

mlip_arena/tasks/eos.py

@@ -71,7 +71,7 @@ def run(
         npoints: The number of points to sample.
 
     Returns:
-        A dictionary containing the EOS data and the bulk modulus.
+        A dictionary containing the EOS data, bulk modulus, equilibrium volume, and equilibrium energy.
     """
     first_relax = OPT(
         atoms=atoms,
@@ -138,4 +138,8 @@ def run(
     return {
         "eos": {"volumes": volumes, "energies": energies},
         "K": bm.b0_GPa,
+        "b0": bm.b0,
+        "b1": bm.b1,
+        "e0": bm.e0,
+        "v0": bm.v0,
     }

tests/test_eos.py

@@ -45,4 +45,4 @@ def test_eos(model: MLIPEnum):
             calculator_name=model.name,
         )
 
-        assert isinstance(result["K"], float)
+        assert isinstance(result["b0"], float)

tests/test_md.py

@@ -19,7 +19,8 @@ def test_nve(model: MLIPEnum):
         calculator_kwargs={},
         ensemble="nve",
         dynamics="velocityverlet",
-        total_time=3,
+        total_time=10,
+        time_step=2,
     )
 
     assert isinstance(result["atoms"].get_potential_energy(), float)