Add Pico simulator and shared protocol layer

simulator/pico_sim.py

@@ -0,0 +1,42 @@
+from protocol import (
+    MessageType,
+    status_request,
+    set_relay_request,
+    enable_wifi_request,
+    toggle_ignition_request,
+    toggle_sensor_fault_request,
+)
+
+
+class PicoSimulator:
+    def __init__(self, controller):
+        self.controller = controller
+        self.last_status = None
+        self.primary_link = "rs485"
+        self.backup_link_available = True
+
+    def send_message(self, message):
+        """
+        This simulates the Pico sending a protocol message to the ESP32.
+
+        Later, this is where RS-485 serial communication will replace
+        the direct Python method call.
+        """
+        return self.controller.handle_message(message)
+
+    def get_status(self):
+        response = self.send_message(status_request())
+        self.last_status = response["data"]
+        return self.last_status
+
+    def set_relay(self, relay, state):
+        return self.send_message(set_relay_request(relay, state))
+
+    def enable_wifi(self, minutes=10):
+        return self.send_message(enable_wifi_request(minutes))
+
+    def toggle_ignition(self):
+        return self.send_message(toggle_ignition_request())
+
+    def toggle_sensor_fault(self, sensor):
+        return self.send_message(toggle_sensor_fault_request(sensor))