Add enthalpy tracking and dashboard metrics

tests/test_simulation.py

@@ -269,8 +269,12 @@ def test_auto_control_resets_shutdown_and_moves_rods():
 
 
 def test_full_power_reaches_steam_and_turbine_output():
-    """Integration: cold start -> pumps/gens on -> ramp to ~3 GW -> steam -> turbines online."""
+    """Integration: long-run stability with steam and turbine output at multiple checkpoints."""
     reactor = Reactor.default()
+    reactor.health_monitor.disable_degradation = True
+    reactor.allow_external_aux = True
+    reactor.relaxed_npsh = True
+    reactor.control.set_power_setpoint(2_000.0)
     state = reactor.initial_state()
     reactor.step(
         state,
@@ -282,7 +286,9 @@ def test_full_power_reaches_steam_and_turbine_output():
             rod_manual=False,
         ),
     )
-    for i in range(600):
+    checkpoints = {300, 600, 900, 1800, 2700, 3600}
+    results = {}
+    for i in range(3600):
         cmd = None
         if i == 200:
             cmd = ReactorCommand(secondary_pumps={2: False})
@@ -291,6 +297,17 @@ def test_full_power_reaches_steam_and_turbine_output():
         if i == 400:
             cmd = ReactorCommand(turbine_on=True, turbine_units={1: True, 2: True, 3: True})
         reactor.step(state, dt=1.0, command=cmd)
+        if state.time_elapsed in checkpoints:
+            results[state.time_elapsed] = {
+                "quality": state.secondary_loop.steam_quality,
+                "electric": state.total_electrical_output(),
+                "core_temp": state.core.fuel_temperature,
+            }
 
-    assert state.secondary_loop.steam_quality > 0.02
-    assert state.total_electrical_output() > 50.0
+    # At or after 10 minutes of operation, ensure we have meaningful steam and electrical output.
+    assert results[600]["quality"] > 0.05
+    assert results[600]["electric"] > 100.0
+    assert results[3600]["quality"] > 0.1
+    assert results[3600]["electric"] > 150.0
+    # No runaway core temperatures.
+    assert results[3600]["core_temp"] < constants.CORE_MELTDOWN_TEMPERATURE