Add setting to control autosave interval mode

src/table/settings/settings.ini

@@ -4525,6 +4525,16 @@ strval   = STR_GAME_OPTIONS_AUTOSAVE_DROPDOWN_EVERY_MINUTES_CUSTOM
 post_cb  = AutosaveModeChanged
 cat      = SC_BASIC
 
+[SDTC_BOOL]
+var      = gui.autosave_realtime
+flags    = SF_NOT_IN_SAVE | SF_NO_NETWORK_SYNC
+def      = true
+str      = STR_CONFIG_SETTING_AUTOSAVE_REALTIME
+strhelp  = STR_CONFIG_SETTING_AUTOSAVE_REALTIME_HELPTEXT
+post_cb  = AutosaveModeChanged
+patchcat = SC_PATCH
+cat      = SC_EXPERT
+
 [SDTC_BOOL]
 var      = gui.threaded_saves
 flags    = SF_NOT_IN_SAVE | SF_NO_NETWORK_SYNC