Load Maps on Round Start, not Round Restart v3 (#6989)

* Load Maps on Round Start, not Round Restart

* Fix admin log test.
It assumed maps/grids existed during pre-round, wihch is not a valid assumption anymore after this PR.

* Shutdown server if round fails to start 5 times.

* Fix bugs with round starting flag.

* Make StartRound not async, synchronously get new round ID from DB.

* Handle StationId.Invalid in PickBestAvailableJob
Instead of crashing, return null.
SpawnPlayer will handle this by making the player an observer or returning them to the lobby.

Content.Server/GameTicking/GameTicker.CVars.cs

@@ -27,6 +27,11 @@ namespace Content.Server.GameTicking
         [ViewVariables]
         public float MaxStationOffset { get; private set; } = 0f;
 
+#if EXCEPTION_TOLERANCE
+        [ViewVariables]
+        public int RoundStartFailShutdownCount { get; private set; } = 0;
+#endif
+
         private void InitializeCVars()
         {
             _configurationManager.OnValueChanged(CCVars.GameLobbyEnabled, value => LobbyEnabled = value, true);
@@ -37,6 +42,9 @@ namespace Content.Server.GameTicking
             _configurationManager.OnValueChanged(CCVars.StationOffset, value => StationOffset = value, true);
             _configurationManager.OnValueChanged(CCVars.StationRotation, value => StationRotation = value, true);
             _configurationManager.OnValueChanged(CCVars.MaxStationOffset, value => MaxStationOffset = value, true);
+#if EXCEPTION_TOLERANCE
+            _configurationManager.OnValueChanged(CCVars.RoundStartFailShutdownCount, value => RoundStartFailShutdownCount = value, true);
+#endif
         }
     }
 }