[Obs AI Assistant] Remove prompts from recall ranking Telemetry event (#214573)

Closes https://github.com/elastic/obs-ai-assistant-team/issues/224

## Summary

Relates to https://github.com/elastic/obs-ai-assistant-team/issues/186

Removes the prompts from the recall ranking telemetry event.

### Checklist

- [x] The PR description includes the appropriate Release Notes section,
and the correct `release_note:*` label is applied per the
[guidelines](https://www.elastic.co/guide/en/kibana/master/contributing.html#kibana-release-notes-process)

x-pack/platform/packages/shared/kbn-ai-assistant/src/chat/chat_body.tsx

@@ -38,6 +38,7 @@ import {
 import type { AuthenticatedUser } from '@kbn/security-plugin/common';
 import { findLastIndex } from 'lodash';
 import React, { useCallback, useEffect, useRef, useState } from 'react';
+import { ChatFeedback } from '@kbn/observability-ai-assistant-plugin/public/analytics/schemas/chat_feedback';
 import type { UseKnowledgeBaseResult } from '../hooks/use_knowledge_base';
 import { ASSISTANT_SETUP_TITLE, EMPTY_CONVERSATION_TITLE, UPGRADE_LICENSE_TITLE } from '../i18n';
 import { useAIAssistantChatService } from '../hooks/use_ai_assistant_chat_service';
@@ -220,13 +221,24 @@ export function ChatBody({
     if (conversation.value?.conversation && 'user' in conversation.value) {
       const {
         messages: _removedMessages, // Exclude messages
-        conversation: { title: _removedTitle, ...conversationRest }, // Exclude title
-        ...rest
+        systemMessage: _removedSystemMessage, // Exclude systemMessage
+        conversation: { title: _removedTitle, id, last_updated: lastUpdated }, // Exclude title
+        user,
+        labels,
+        numeric_labels: numericLabels,
+        namespace,
+        public: isPublic,
+        '@timestamp': timestamp,
       } = conversation.value;
 
-      const conversationWithoutMessagesAndTitle = {
-        ...rest,
-        conversation: conversationRest,
+      const conversationWithoutMessagesAndTitle: ChatFeedback['conversation'] = {
+        '@timestamp': timestamp,
+        user,
+        labels,
+        numeric_labels: numericLabels,
+        namespace,
+        public: isPublic,
+        conversation: { id, last_updated: lastUpdated },
       };
 
       chatService.sendAnalyticsEvent({

x-pack/platform/plugins/shared/observability_ai_assistant/server/analytics/recall_ranking.ts

@@ -8,33 +8,19 @@
 import { RootSchema, EventTypeOpts } from '@kbn/core/server';
 
 interface ScoredDocument {
-  content: string;
   elserScore: number;
   llmScore: number;
 }
 
 export interface RecallRanking {
-  prompt: string;
   scoredDocuments: ScoredDocument[];
 }
 
 const schema: RootSchema<RecallRanking> = {
-  prompt: {
-    type: 'text',
-    _meta: {
-      description: 'The user prompt that was used for the ELSER text_expansion',
-    },
-  },
   scoredDocuments: {
     type: 'array',
     items: {
       properties: {
-        content: {
-          type: 'text',
-          _meta: {
-            description: 'The raw content of the recalled document',
-          },
-        },
         elserScore: {
           type: 'float',
           _meta: {

x-pack/platform/plugins/shared/observability_ai_assistant/server/utils/recall/recall_and_score.ts

@@ -68,11 +68,9 @@ export async function recallAndScore({
     });
 
     analytics.reportEvent<RecallRanking>(recallRankingEventType, {
-      prompt: queries.map((query) => query.text).join('\n\n'),
       scoredDocuments: suggestions.map((suggestion) => {
         const llmScore = scores.find((score) => score.id === suggestion.id);
         return {
-          content: suggestion.text,
           elserScore: suggestion.score ?? -1,
           llmScore: llmScore ? llmScore.score : -1,
         };