Merged PR 48250: [internal/release/9.3] Fix report generation

The .NET side code for the `ScenarioRunResult` was recently changed (##5998) to include `ChatResponse` (which can contain multiple `ChatMessage`s) in place of a single `ChatMessage`. Unfortunately, we missed updating the TypeScript reporting code to account for this.

This change fixes the problem by updating the deserialization code in TypeScript to match what .NET code serializes.

Cherry-picked from commit `41bbedd0` (#6061)

Author: Shyam Namboodiripad

src/Libraries/Microsoft.Extensions.AI.Evaluation.Reporting/TypeScript/components/EvalTypes.d.ts

@@ -13,10 +13,14 @@ type ScenarioRunResult = {
     executionName: string;
     creationTime?: string;
     messages: ChatMessage[];
-    modelResponse: ChatMessage;
+    modelResponse: ChatResponse;
     evaluationResult: EvaluationResult;
 };
 
+type ChatResponse = {
+    messages: ChatMessage[];
+}
+
 type ChatMessage = {
     authorName?: string;
     role: string;

src/Libraries/Microsoft.Extensions.AI.Evaluation.Reporting/TypeScript/components/Summary.ts

@@ -145,7 +145,7 @@ const isTextContent = (content: AIContent): content is TextContent => {
     return (content as TextContent).text !== undefined;
 };
 
-export const getPromptDetails = (messages: ChatMessage[], modelResponse?: ChatMessage): {history:string, response: string}=> {
+export const getPromptDetails = (messages: ChatMessage[], modelResponse?: ChatResponse): {history:string, response: string}=> {
     let history: string = "";
     if (messages.length === 1) {
         history = messages[0].contents.map(c => (c as TextContent).text).join("\n");
@@ -163,7 +163,7 @@ export const getPromptDetails = (messages: ChatMessage[], modelResponse?: ChatMe
         history = historyItems.join("\n\n");
     }
 
-    const response: string = modelResponse?.contents.map(c => (c as TextContent).text).join("\n") ?? "";
+    const response: string = modelResponse?.messages.map(m => m.contents.map(c => (c as TextContent).text).join("\n") ?? "").join("\n") ?? "";
 
     return { history, response };
 };