Issue X2CommunityCore#1406 - Add docs

X2WOTCCommunityHighlander/Src/XComGame/Classes/X2TacticalGameRuleset.uc

@@ -3893,6 +3893,17 @@ Begin:
 	}
 
 	// Start Issue #1406
+	/// HL-Docs: feature:PostMissionIntroKismet; issue:1406; tags:tactical
+	/// This event triggers after mission intro kismet has been completed.
+	/// For example, a mission such as Supply Extraction spawns their objective crates
+	/// when `'SeqEvent_OnTacticalMissionStartBlocking'` has been triggered,
+	/// which happens after `'OnBeginTacticalPlay'` event has already been triggered.
+	/// As such, you don't have a handle for anything the mission kismet causes before your first XCOM turn.
+	/// This event can be considered a later alternative to `'OnBeginTacticalPlay'` event.
+	///
+	/// ```unrealscript
+	/// EventID: PostMissionIntroKismet
+	/// ```
 	`XEVENTMGR.TriggerEvent('PostMissionIntroKismet',,,);
 	// End Issue #1406