Show the status of each flight in the UI.

https://github.com/dcs-liberation/dcs_liberation/issues/1704

qt_ui/simcontroller.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 import logging
-from datetime import datetime
+from datetime import datetime, timedelta
 from pathlib import Path
 from typing import Callable, Optional, TYPE_CHECKING
 
@@ -40,6 +40,12 @@ class SimController(QObject):
             return None
         return self.game_loop.current_time_in_sim
 
+    @property
+    def elapsed_time(self) -> timedelta:
+        if self.game_loop is None:
+            return timedelta()
+        return self.game_loop.elapsed_time
+
     def set_game(self, game: Optional[Game]) -> None:
         self.recreate_game_loop(game)
         self.sim_speed_reset.emit(SimSpeedSetting.PAUSED)