[Discover][Obs ai assistant] Set the index pattern on the context api…

… to generate correct ES|QL queries etc (#181001)

## Summary

Sets the index pattern correctly in the obs ai assistant. 
The Obs ai assistant is part of Discover in serverless Oblt project and
can also be set up everywhere from the Observability AI Assistant scope
advanced setting. It is a very useful tool for the Discover users and
for moving from KQL to ES|QL world.

This is important for prompts such as:

- Transform the KQL and filters to ES|QL


![meow](https://github.com/elastic/kibana/assets/17003240/e9b1be13-667a-4fdb-addb-fb77e485b99e)

- More

<img width="579" alt="image"
src="https://github.com/elastic/kibana/assets/17003240/91b6b0ac-754f-47f3-98a2-ed09e7be646b">


Other interesting prompts:

- Equivalent of KQL of where filters

<img width="640" alt="image"
src="https://github.com/elastic/kibana/assets/17003240/f203bc5e-a037-49c9-9e6c-5e68c9fcb864">

- Explain the ES|QL query
<img width="658" alt="image"
src="https://github.com/elastic/kibana/assets/17003240/b2f9abfb-577d-4c06-b715-553ebd626e28">


- Run questions on your dataset and unified search bar selection
<img width="687" alt="image"
src="https://github.com/elastic/kibana/assets/17003240/e095ced8-5bf9-4846-ac54-644c4fd8de04">

---------

Co-authored-by: kibanamachine <[email protected]>

src/plugins/discover/kibana.jsonc

@@ -37,7 +37,8 @@
       "savedObjectsTaggingOss",
       "lens",
       "noDataPage",
-      "globalSearch"
+      "globalSearch",
+      "observabilityAIAssistant"
     ],
     "requiredBundles": ["kibanaUtils", "kibanaReact", "unifiedSearch", "savedObjects"],
     "extraPublicDirs": ["common"]

src/plugins/discover/public/application/main/components/layout/discover_layout.tsx

@@ -71,6 +71,7 @@ export function DiscoverLayout({ stateContainer }: DiscoverLayoutProps) {
     filterManager,
     history,
     spaces,
+    observabilityAIAssistant,
   } = useDiscoverServices();
   const pageBackgroundColor = useEuiBackgroundColor('plain');
   const globalQueryState = data.query.getState();
@@ -132,6 +133,16 @@ export function DiscoverLayout({ stateContainer }: DiscoverLayoutProps) {
     sort,
   });
 
+  // The assistant is getting the state from the url correctly
+  // expect from the index pattern where we have only the dataview id
+  useEffect(() => {
+    return observabilityAIAssistant?.service.setScreenContext({
+      screenDescription: `The user is looking at the Discover view on the ${
+        isPlainRecord ? 'ES|QL' : 'dataView'
+      } mode. The index pattern is the ${dataView.getIndexPattern()}`,
+    });
+  }, [dataView, isPlainRecord, observabilityAIAssistant?.service]);
+
   const onAddFilter = useCallback(
     (field: DataViewField | string, values: unknown, operation: '+' | '-') => {
       const fieldName = typeof field === 'string' ? field : field.name;

src/plugins/discover/public/build_services.ts

@@ -54,6 +54,7 @@ import type { LensPublicStart } from '@kbn/lens-plugin/public';
 import type { UiActionsStart } from '@kbn/ui-actions-plugin/public';
 import type { SettingsStart } from '@kbn/core-ui-settings-browser';
 import type { ContentClient } from '@kbn/content-management-plugin/public';
+import type { ObservabilityAIAssistantPublicStart } from '@kbn/observability-ai-assistant-plugin/public';
 import { memoize, noop } from 'lodash';
 import type { NoDataPagePluginStart } from '@kbn/no-data-page-plugin/public';
 import { DiscoverStartPlugins } from './plugin';
@@ -123,6 +124,7 @@ export interface DiscoverServices {
   uiActions: UiActionsStart;
   contentClient: ContentClient;
   noDataPage?: NoDataPagePluginStart;
+  observabilityAIAssistant?: ObservabilityAIAssistantPublicStart;
 }
 
 export const buildServices = memoize(
@@ -203,6 +205,7 @@ export const buildServices = memoize(
       uiActions: plugins.uiActions,
       contentClient: plugins.contentManagement.client,
       noDataPage: plugins.noDataPage,
+      observabilityAIAssistant: plugins.observabilityAIAssistant,
     };
   }
 );

src/plugins/discover/public/plugin.tsx

@@ -46,6 +46,10 @@ import { setStateToKbnUrl } from '@kbn/kibana-utils-plugin/public';
 import type { LensPublicStart } from '@kbn/lens-plugin/public';
 import { TRUNCATE_MAX_HEIGHT, ENABLE_ESQL } from '@kbn/discover-utils';
 import type { NoDataPagePluginStart } from '@kbn/no-data-page-plugin/public';
+import type {
+  ObservabilityAIAssistantPublicSetup,
+  ObservabilityAIAssistantPublicStart,
+} from '@kbn/observability-ai-assistant-plugin/public';
 import { PLUGIN_ID } from '../common';
 import { registerFeature } from './register_feature';
 import { buildServices, UrlTracker } from './build_services';
@@ -166,6 +170,7 @@ export interface DiscoverSetupPlugins {
   data: DataPublicPluginSetup;
   expressions: ExpressionsSetup;
   globalSearch?: GlobalSearchPluginSetup;
+  observabilityAIAssistant?: ObservabilityAIAssistantPublicSetup;
 }
 
 /**
@@ -196,6 +201,7 @@ export interface DiscoverStartPlugins {
   lens: LensPublicStart;
   contentManagement: ContentManagementPublicStart;
   noDataPage?: NoDataPagePluginStart;
+  observabilityAIAssistant?: ObservabilityAIAssistantPublicStart;
 }
 
 export type StartRenderServices = Pick<CoreStart, 'analytics' | 'i18n' | 'theme'>;

src/plugins/discover/tsconfig.json

@@ -83,7 +83,8 @@
     "@kbn/deeplinks-analytics",
     "@kbn/shared-ux-markdown",
     "@kbn/data-view-utils",
-    "@kbn/presentation-publishing"
+    "@kbn/presentation-publishing",
+    "@kbn/observability-ai-assistant-plugin"
   ],
   "exclude": ["target/**/*"]
 }