Add mission name as hook variable (#6699)

Author: MjnMixael

code/mission/missioncampaign.cpp

@@ -1160,7 +1160,9 @@ void mission_campaign_mission_over(bool do_next_mission)
 		}
 
 		// runs the new scripting conditional hook, "On Campaign Mission Accept" --wookieejedi
-		scripting::hooks::OnCampaignMissionAccept->run();
+		scripting::hooks::OnCampaignMissionAccept->run(
+			scripting::hook_param_list(scripting::hook_param("Mission", 's', mission_obj->name)
+		));
 
 	} else {
 		// free up the goals and events which were just malloced.  It's kind of like erasing any fact

code/scripting/global_hooks.cpp

@@ -67,7 +67,9 @@ const std::shared_ptr<Hook<>> OnLoadComplete =
 
 const std::shared_ptr<Hook<>> OnCampaignMissionAccept = Hook<>::Factory("On Campaign Mission Accept",
 	"Invoked after a campaign mission once the player accepts the result and moves on to the next mission instead of replaying it.",
-	{});
+	{
+		{"Mission", "string", "The filename of the mission that was just accepted."}
+	});
 
 const std::shared_ptr<Hook<>> OnBriefStage = Hook<>::Factory("On Briefing Stage",
 	"Invoked for each briefing stage what it is shown.",