Fix crash if log window is open when entering mission.

Use signal to append text to LogWindow to avoid crash from crossing thread boundaries.
Change modal flag to enable interacting with LogWindow while the mission is running

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/1493

qt_ui/windows/QWaitingForMissionResultWindow.py

@@ -2,11 +2,11 @@ from __future__ import annotations
 
 import json
 import os
-from typing import Sized
+from typing import Sized, Optional
 
 from PySide2 import QtCore
 from PySide2.QtCore import QObject, Qt, Signal
-from PySide2.QtGui import QIcon, QMovie, QPixmap
+from PySide2.QtGui import QIcon, QMovie, QPixmap, QWindow
 from PySide2.QtWidgets import (
     QDialog,
     QFileDialog,
@@ -17,6 +17,7 @@ from PySide2.QtWidgets import (
     QMessageBox,
     QPushButton,
     QTextBrowser,
+    QWidget,
 )
 from jinja2 import Environment, FileSystemLoader, select_autoescape
 
@@ -49,9 +50,15 @@ DebriefingFileWrittenSignal()
 
 
 class QWaitingForMissionResultWindow(QDialog):
-    def __init__(self, gameEvent: Event, game: Game, unit_map: UnitMap) -> None:
-        super(QWaitingForMissionResultWindow, self).__init__()
-        self.setModal(True)
+    def __init__(
+        self,
+        gameEvent: Event,
+        game: Game,
+        unit_map: UnitMap,
+        parent: Optional[QWidget] = None,
+    ) -> None:
+        super(QWaitingForMissionResultWindow, self).__init__(parent=parent)
+        self.setWindowModality(QtCore.Qt.WindowModal)
         self.gameEvent = gameEvent
         self.game = game
         self.unit_map = unit_map