feat(display): add configurable multi-backend display system

engine/app.py

@@ -33,13 +33,25 @@ from engine.websocket_display import WebSocketDisplay
 
 
 def _get_display():
-    """Get the appropriate display based on config."""
-    if config.WEBSOCKET:
+    """Get the appropriate display(s) based on config."""
+    from engine.display import MultiDisplay, TerminalDisplay
+
+    displays = []
+
+    if config.DISPLAY in ("terminal", "both"):
+        displays.append(TerminalDisplay())
+
+    if config.DISPLAY in ("websocket", "both") or config.WEBSOCKET:
         ws = WebSocketDisplay(host="0.0.0.0", port=config.WEBSOCKET_PORT)
         ws.start_server()
         ws.start_http_server()
-        return ws
-    return None
+        displays.append(ws)
+
+    if not displays:
+        return None
+    if len(displays) == 1:
+        return displays[0]
+    return MultiDisplay(displays)
 
 
 TITLE = [