[ML] Fixes unnecessary ML services initialization during plugin setup (…

…#193153)

A change to the cases registration in
#183423 added a call to
`getMlServices` during plugin setup.
In this function many services are initialized including the ML
capabilities service which contains a timed refresh of the ML
capabilities (every 5mins). This means when using any page in kibana,
`ml_capabilities` is called every 5min.
This is very obvious when you leave a page open for a long time.

![image](https://github.com/user-attachments/assets/2f24285e-b093-434f-9ef4-023ff89158bc)

It is not unnecessary to call `getMlServices` during plugin setup and
instead can be called during the lazy loading of the single metric
viewer component, where it is used.

x-pack/plugins/ml/public/cases/register_cases_attachments.ts

@@ -10,21 +10,14 @@ import type { CoreStart } from '@kbn/core/public';
 import { registerAnomalyChartsCasesAttachment } from './register_anomaly_charts_attachment';
 import { registerSingleMetricViewerCasesAttachment } from './register_single_metric_viewer_attachment';
 import type { MlStartDependencies } from '../plugin';
-import type { SingleMetricViewerServices } from '../embeddables/types';
 import { registerAnomalySwimLaneCasesAttachment } from './register_anomaly_swim_lane_attachment';
 
 export function registerCasesAttachments(
   cases: CasesPublicSetup,
   coreStart: CoreStart,
-  pluginStart: MlStartDependencies,
-  singleMetricViewerServices: SingleMetricViewerServices
+  pluginStart: MlStartDependencies
 ) {
   registerAnomalySwimLaneCasesAttachment(cases, pluginStart);
   registerAnomalyChartsCasesAttachment(cases, coreStart, pluginStart);
-  registerSingleMetricViewerCasesAttachment(
-    cases,
-    coreStart,
-    pluginStart,
-    singleMetricViewerServices
-  );
+  registerSingleMetricViewerCasesAttachment(cases, coreStart, pluginStart);
 }

x-pack/plugins/ml/public/cases/register_single_metric_viewer_attachment.tsx

@@ -14,21 +14,14 @@ import { PLUGIN_ICON } from '../../common/constants/app';
 import { CASE_ATTACHMENT_TYPE_ID_SINGLE_METRIC_VIEWER } from '../../common/constants/cases';
 import type { MlStartDependencies } from '../plugin';
 import { getSingleMetricViewerComponent } from '../shared_components/single_metric_viewer';
-import type { SingleMetricViewerServices } from '../embeddables/types';
 import type { MlDependencies } from '../application/app';
+import { getMlServices } from '../embeddables/single_metric_viewer/get_services';
 
 export function registerSingleMetricViewerCasesAttachment(
   cases: CasesPublicSetup,
   coreStart: CoreStart,
-  pluginStart: MlStartDependencies,
-  mlServices: SingleMetricViewerServices
+  pluginStart: MlStartDependencies
 ) {
-  const SingleMetricViewerComponent = getSingleMetricViewerComponent(
-    coreStart,
-    pluginStart as MlDependencies,
-    mlServices
-  );
-
   cases.attachmentFramework.registerPersistableState({
     id: CASE_ATTACHMENT_TYPE_ID_SINGLE_METRIC_VIEWER,
     icon: PLUGIN_ICON,
@@ -44,7 +37,15 @@ export function registerSingleMetricViewerCasesAttachment(
       ),
       timelineAvatar: PLUGIN_ICON,
       children: React.lazy(async () => {
-        const { initComponent } = await import('./single_metric_viewer_attachment');
+        const [{ initComponent }, mlServices] = await Promise.all([
+          import('./single_metric_viewer_attachment'),
+          getMlServices(coreStart, pluginStart),
+        ]);
+        const SingleMetricViewerComponent = getSingleMetricViewerComponent(
+          coreStart,
+          pluginStart as MlDependencies,
+          mlServices
+        );
         return {
           default: initComponent(pluginStart.fieldFormats, SingleMetricViewerComponent),
         };

x-pack/plugins/ml/public/plugin.ts

@@ -73,7 +73,6 @@ import type { ElasticModels } from './application/services/elastic_models_servic
 import type { MlApi } from './application/services/ml_api_service';
 import type { MlCapabilities } from '../common/types/capabilities';
 import { AnomalySwimLane } from './shared_components';
-import { getMlServices } from './embeddables/single_metric_viewer/get_services';
 
 export interface MlStartDependencies {
   cases?: CasesPublicStart;
@@ -275,8 +274,7 @@ export class MlPlugin implements Plugin<MlPluginSetup, MlPluginStart> {
                 registerEmbeddables(pluginsSetup.embeddable, core);
 
                 if (pluginsSetup.cases) {
-                  const mlServices = await getMlServices(coreStart, pluginStart);
-                  registerCasesAttachments(pluginsSetup.cases, coreStart, pluginStart, mlServices);
+                  registerCasesAttachments(pluginsSetup.cases, coreStart, pluginStart);
                 }
 
                 if (pluginsSetup.maps) {