Chat Telemetry: Restores prompt and response text recording (#5553)

Previously, chat telemetry events were not capturing `promptText` and
`responseText` due to the asynchronous nature of the
`truncatePromptString` function, which was modified in a recent pull
request(#5231).

Now, we have added the proper `await` calls when using
`truncatePromptString`, re-enabling the collection of this data for chat
telemetry events.

Key changes:
1. Added `await` to `ChatController` where `truncatePromptString` is
being used
2. Made `addBotMessage` an async func

## Test plan
Tested locally and verified `promptText` and `responseText` are being
recorded again.


https://github.com/user-attachments/assets/b3952819-0945-4162-baf7-d98704aec21d


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## Changelog

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vscode/src/chat/chat-view/ChatController.ts

@@ -911,7 +911,8 @@ export class ChatController implements vscode.Disposable, vscode.WebviewViewProv
                 // V2 telemetry exports privateMetadata only for DotCom users
                 // the condition below is an additional safeguard measure
                 promptText:
-                    isDotCom(authStatus) && truncatePromptString(inputText, CHAT_INPUT_TOKEN_BUDGET),
+                    isDotCom(authStatus) &&
+                    (await truncatePromptString(inputText, CHAT_INPUT_TOKEN_BUDGET)),
             },
             billingMetadata: {
                 product: 'cody',
@@ -1423,7 +1424,7 @@ export class ChatController implements vscode.Disposable, vscode.WebviewViewProv
     /**
      * Finalizes adding a bot message to the chat model and triggers an update to the view.
      */
-    private addBotMessage(requestID: string, rawResponse: PromptString): void {
+    private async addBotMessage(requestID: string, rawResponse: PromptString): Promise<void> {
         const messageText = reformatBotMessageForChat(rawResponse)
         this.chatModel.addBotMessage({ text: messageText })
         void this.saveSession()
@@ -1448,7 +1449,8 @@ export class ChatController implements vscode.Disposable, vscode.WebviewViewProv
                 // V2 telemetry exports privateMetadata only for DotCom users
                 // the condition below is an aditional safegaurd measure
                 responseText:
-                    isDotCom(authStatus) && truncatePromptString(messageText, CHAT_OUTPUT_TOKEN_BUDGET),
+                    isDotCom(authStatus) &&
+                    (await truncatePromptString(messageText, CHAT_OUTPUT_TOKEN_BUDGET)),
                 chatModel: this.chatModel.modelID,
             },
             billingMetadata: {
@@ -1798,7 +1800,8 @@ export class ChatController implements vscode.Disposable, vscode.WebviewViewProv
                 // V2 telemetry exports privateMetadata only for DotCom users
                 // the condition below is an additional safeguard measure
                 promptText:
-                    isDotCom(authStatus) && truncatePromptString(inputText, CHAT_INPUT_TOKEN_BUDGET),
+                    isDotCom(authStatus) &&
+                    (await truncatePromptString(inputText, CHAT_INPUT_TOKEN_BUDGET)),
                 gitMetadata,
             },
             billingMetadata: {