[9.4] chore: lazy-load server plugin modules (kibana-security) (#266614) (#266699)

# Backport

This will backport the following commits from `main` to `9.4`:
- [chore: lazy-load server plugin modules (kibana-security)
(#266614)](#266614)

<!--- Backport version: 9.6.6 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sorenlouv/backport)

<!--BACKPORT [{"author":{"name":"Alejandro Fernández
Haro","email":"alejandro.haro@elastic.co"},"sourceCommit":{"committedDate":"2026-04-30T14:28:34Z","message":"chore:
lazy-load server plugin modules (kibana-security) (#266614)\n\n##
Summary\n\nLazy-load server plugin implementations via `await
import('./plugin')`\n(and related entrypoint adjustments) from
`server/index.ts`, consistent\nwith
https://github.com/elastic/kibana/pull/170856.\n\nThe migration in
#170856 reduced **startup time by ~4 seconds** in\nmeasured scenarios.
**Memory savings were not quantified but are\nexpected.**\n\n##
CODEOWNERS\n\n- `examples/eso_model_version_example` →
@elastic/kibana-security\n- `packages/kbn-mock-idp-plugin` →
@elastic/kibana-security\n\n## Follow-up\n\n-
#171080 — add an ESLint rule\nso
new plugins follow this pattern.\n\n---\n\n**Disclaimer:** This PR was
prepared with AI assistance (Cursor /\nClaude); please review
thoroughly.","sha":"29dbe1df7a1b0b9dfca7371436eff6bf28c1dae7","branchLabelMapping":{"^v9.5.0$":"main","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["release_note:skip","backport:version","v9.4.0","v9.5.0"],"title":"chore:
lazy-load server plugin modules
(kibana-security)","number":266614,"url":"https://github.com/elastic/kibana/pull/266614","mergeCommit":{"message":"chore:
lazy-load server plugin modules (kibana-security) (#266614)\n\n##
Summary\n\nLazy-load server plugin implementations via `await
import('./plugin')`\n(and related entrypoint adjustments) from
`server/index.ts`, consistent\nwith
https://github.com/elastic/kibana/pull/170856.\n\nThe migration in
#170856 reduced **startup time by ~4 seconds** in\nmeasured scenarios.
**Memory savings were not quantified but are\nexpected.**\n\n##
CODEOWNERS\n\n- `examples/eso_model_version_example` →
@elastic/kibana-security\n- `packages/kbn-mock-idp-plugin` →
@elastic/kibana-security\n\n## Follow-up\n\n-
#171080 — add an ESLint rule\nso
new plugins follow this pattern.\n\n---\n\n**Disclaimer:** This PR was
prepared with AI assistance (Cursor /\nClaude); please review
thoroughly.","sha":"29dbe1df7a1b0b9dfca7371436eff6bf28c1dae7"}},"sourceBranch":"main","suggestedTargetBranches":["9.4"],"targetPullRequestStates":[{"branch":"9.4","label":"v9.4.0","branchLabelMappingKey":"^v(\\d+).(\\d+).\\d+$","isSourceBranch":false,"state":"NOT_CREATED"},{"branch":"main","label":"v9.5.0","branchLabelMappingKey":"^v9.5.0$","isSourceBranch":true,"state":"MERGED","url":"https://github.com/elastic/kibana/pull/266614","number":266614,"mergeCommit":{"message":"chore:
lazy-load server plugin modules (kibana-security) (#266614)\n\n##
Summary\n\nLazy-load server plugin implementations via `await
import('./plugin')`\n(and related entrypoint adjustments) from
`server/index.ts`, consistent\nwith
https://github.com/elastic/kibana/pull/170856.\n\nThe migration in
#170856 reduced **startup time by ~4 seconds** in\nmeasured scenarios.
**Memory savings were not quantified but are\nexpected.**\n\n##
CODEOWNERS\n\n- `examples/eso_model_version_example` →
@elastic/kibana-security\n- `packages/kbn-mock-idp-plugin` →
@elastic/kibana-security\n\n## Follow-up\n\n-
#171080 — add an ESLint rule\nso
new plugins follow this pattern.\n\n---\n\n**Disclaimer:** This PR was
prepared with AI assistance (Cursor /\nClaude); please review
thoroughly.","sha":"29dbe1df7a1b0b9dfca7371436eff6bf28c1dae7"}}]}]
BACKPORT-->

Co-authored-by: Alejandro Fernández Haro <alejandro.haro@elastic.co>

Author: kibanamachine

examples/eso_model_version_example/server/index.ts

@@ -8,6 +8,8 @@
  */
 
 import type { PluginInitializer } from '@kbn/core/server';
-import { EsoModelVersionExample } from './plugin';
 
-export const plugin: PluginInitializer<void, void> = async () => new EsoModelVersionExample();
+export const plugin: PluginInitializer<void, void> = async () => {
+  const { EsoModelVersionExample } = await import('./plugin');
+  return new EsoModelVersionExample();
+};

packages/kbn-mock-idp-plugin/moon.yml

@@ -36,6 +36,7 @@ dependsOn:
   - '@kbn/core-http-server'
   - '@kbn/core-http-server-utils'
   - '@kbn/i18n'
+  - '@kbn/core'
 tags:
   - plugin
   - dev

packages/kbn-mock-idp-plugin/server/index.ts

@@ -7,10 +7,16 @@
  * License v3.0 only", or the "Server Side Public License, v 1".
  */
 
+import type { PluginInitializerContext } from '@kbn/core/server';
+
 import { ConfigSchema } from './config';
 
 export type { CreateSAMLResponseParams } from './plugin';
-export { plugin } from './plugin';
+
+export const plugin = async (initializerContext: PluginInitializerContext) => {
+  const { plugin: initPlugin } = await import('./plugin');
+  return initPlugin(initializerContext);
+};
 
 export const config = {
   schema: ConfigSchema,

packages/kbn-mock-idp-plugin/tsconfig.json

@@ -25,5 +25,6 @@
     "@kbn/core-http-server",
     "@kbn/core-http-server-utils",
     "@kbn/i18n",
+    "@kbn/core",
   ]
 }