fix: look ahead for key chain messages

This is required for the railjack quest:
- request has ChainStage 1 when it wants message from index 3
- request has ChainStage 4 when it wants message from index 6
- ...

src/services/itemDataService.ts

@@ -185,13 +185,14 @@ export const getKeyChainMessage = ({ KeyChain, ChainStage }: IKeyChainRequest):
         throw new Error(`KeyChain ${KeyChain} does not contain chain stages`);
     }
 
-    const keyChainStage = chainStages[ChainStage];
+    let i = ChainStage;
-    // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
+    let chainStageMessage = chainStages[i].messageToSendWhenTriggered;
-    if (!keyChainStage) {
+    while (!chainStageMessage) {
-        throw new Error(`KeyChainStage ${ChainStage} not found`);
+        if (++i >= chainStages.length) {
+            break;
+        }
+        chainStageMessage = chainStages[i].messageToSendWhenTriggered;
     }
-
-    const chainStageMessage = keyChainStage.messageToSendWhenTriggered;
 
     if (!chainStageMessage) {
         throw new Error(