feat: add reactor control persistence and tests

src/reactor_sim/consumer.py

@@ -0,0 +1,40 @@
+"""External electrical consumer/load models."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+import logging
+
+LOGGER = logging.getLogger(__name__)
+
+
+@dataclass
+class ElectricalConsumer:
+    name: str
+    demand_mw: float
+    online: bool = False
+    power_received_mw: float = 0.0
+
+    def request_power(self) -> float:
+        return self.demand_mw if self.online else 0.0
+
+    def set_demand(self, demand_mw: float) -> None:
+        previous = self.demand_mw
+        self.demand_mw = max(0.0, demand_mw)
+        LOGGER.info("%s demand %.1f -> %.1f MW", self.name, previous, self.demand_mw)
+
+    def set_online(self, online: bool) -> None:
+        if self.online != online:
+            self.online = online
+            LOGGER.info("%s %s", self.name, "online" if online else "offline")
+
+    def update_power_received(self, supplied_mw: float) -> None:
+        self.power_received_mw = supplied_mw
+        if supplied_mw < self.request_power():
+            LOGGER.warning(
+                "%s under-supplied: %.1f/%.1f MW",
+                self.name,
+                supplied_mw,
+                self.request_power(),
+            )
+