[Guided onboarding] Add guide config route (#146149)

## Summary
Fixes https://github.com/elastic/kibana/issues/145871
Fixes https://github.com/elastic/kibana/issues/145875
This PR adds an internal API endpoint that returns all existing config
guides. The client side code (api service) is updated to use the
endpoint instead of a guide configs file.

Note: This PR deletes the docs link for the kube-state-metrics from the
"Add data" step in the Kubernetes guide. I opened
https://github.com/elastic/kibana/issues/146404 to follow up on this.

### Checklist

- [x] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios

Co-authored-by: kibanamachine <42973632+kibanamachine@users.noreply.github.com>

examples/guided_onboarding_example/public/components/main.tsx

@@ -27,7 +27,6 @@ import {
 } from '@elastic/eui';
 import type { GuideState, GuideStepIds, GuideId, GuideStep } from '@kbn/guided-onboarding';
 import type { GuidedOnboardingPluginStart } from '@kbn/guided-onboarding-plugin/public';
-import { guidesConfig } from '@kbn/guided-onboarding-plugin/public';
 
 interface MainProps {
   guidedOnboarding: GuidedOnboardingPluginStart;
@@ -75,7 +74,15 @@ export const Main = (props: MainProps) => {
   };
 
   const updateGuideState = async () => {
-    const selectedGuideConfig = guidesConfig[selectedGuide!];
+    if (!selectedGuide) {
+      return;
+    }
+
+    const selectedGuideConfig = await guidedOnboardingApi?.getGuideConfig(selectedGuide);
+
+    if (!selectedGuideConfig) {
+      return;
+    }
     const selectedStepIndex = selectedGuideConfig.steps.findIndex(
       (step) => step.id === selectedStep!
     );
@@ -199,7 +206,7 @@ export const Main = (props: MainProps) => {
         </EuiText>
         <EuiSpacer />
         <EuiFlexGroup>
-          {(Object.keys(guidesConfig) as GuideId[]).map((guideId) => {
+          {(['search', 'security', 'observability', 'testGuide'] as GuideId[]).map((guideId) => {
             const guideState = guidesState?.find((guide) => guide.guideId === guideId);
             return (
               <EuiFlexItem>