[Moving] Move Observability Shared folder into `/x-pack/observability…

…_solution` (elastic#177463)

## Summary

This PR is part of the initiative to consolidate Observability plugins
into `x-pack/plugins/observability_solution`.

This PR is strictly a move and an update in references.

This was discussed and agreed upon with the Observability org in the
Observability Office Hours meeting at the end of 2023.

## Related PRs:
- [ ] [Move APM ](elastic#177433)
- [ ] [Move Data Quality](elastic#177456)
- [x] [Move Exploratory
View](elastic#177440)
- [ ] [Move Infra](elastic#177443)
- [X] Move Logs Explorer
- [x] [Move Observability AI
Assistant](elastic#177427)
- [ ] [Move Observability
App](elastic#177437)
- [ ] [Move Observability
Onboarding](elastic#177458)
- [ ] [Move Observability
Shared](elastic#177463) <-- you are here
- [x] [Move Profiling](elastic#177453)
- [ ] [Move Synthetics](elastic#177464) 
- [ ] [Move Uptime](elastic#177466)
- [x] [Move UX](elastic#177470)

---------

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

.eslintrc.js

@@ -917,7 +917,7 @@ module.exports = {
         'x-pack/plugins/observability/**/*.tsx',
         'x-pack/plugins/observability_shared/observability_ai_assistant/**/*.tsx',
         'x-pack/plugins/observability_onboarding/**/*.tsx',
-        'x-pack/plugins/observability_shared/**/*.tsx',
+        'x-pack/plugins/observability_solution/observability_shared/**/*.tsx',
         'x-pack/plugins/observability_solution/profiling/**/*.tsx',
         'x-pack/plugins/synthetics/**/*.tsx',
         'x-pack/plugins/observability_solution/ux/**/*.tsx',
@@ -935,7 +935,7 @@ module.exports = {
         'x-pack/plugins/observability/**/!(*.stories.tsx|*.test.tsx|*.storybook_decorator.tsx|*.mock.tsx)',
         'x-pack/plugins/observability_solution/observability_ai_assistant/**/!(*.stories.tsx|*.test.tsx|*.storybook_decorator.tsx|*.mock.tsx)',
         'x-pack/plugins/observability_onboarding/**/!(*.stories.tsx|*.test.tsx|*.storybook_decorator.tsx|*.mock.tsx)',
-        'x-pack/plugins/observability_shared/**/!(*.stories.tsx|*.test.tsx|*.storybook_decorator.tsx|*.mock.tsx)',
+        'x-pack/plugins/observability_solution/observability_shared/**/!(*.stories.tsx|*.test.tsx|*.storybook_decorator.tsx|*.mock.tsx)',
         'x-pack/plugins/observability_solution/profiling/**/!(*.stories.tsx|*.test.tsx|*.storybook_decorator.tsx|*.mock.tsx)',
         'x-pack/plugins/synthetics/**/!(*.stories.tsx|*.test.tsx|*.storybook_decorator.tsx|*.mock.tsx)',
         'x-pack/plugins/observability_solution/ux/**/!(*.stories.tsx|*.test.tsx|*.storybook_decorator.tsx|*.mock.tsx)',

.github/CODEOWNERS

@@ -577,7 +577,7 @@ x-pack/packages/observability/get_padded_alert_time_range_util @elastic/obs-ux-m
 x-pack/plugins/observability_solution/observability_logs_explorer @elastic/obs-ux-logs-team
 x-pack/plugins/observability_onboarding @elastic/obs-ux-logs-team
 x-pack/plugins/observability @elastic/obs-ux-management-team
-x-pack/plugins/observability_shared @elastic/observability-ui
+x-pack/plugins/observability_solution/observability_shared @elastic/observability-ui
 x-pack/test/security_api_integration/plugins/oidc_provider @elastic/kibana-security
 test/common/plugins/otel_metrics @elastic/obs-ux-infra_services-team
 packages/kbn-openapi-bundler @elastic/security-detection-rule-management
@@ -1093,7 +1093,7 @@ x-pack/plugins/infra/server/lib/alerting @elastic/obs-ux-management-team
 /x-pack/test/functional/apps/observability_logs_explorer @elastic/obs-ux-logs-team
 
 # Observability onboarding tour
-/x-pack/plugins/observability_shared/public/components/tour @elastic/platform-onboarding
+/x-pack/plugins/observability_solution/observability_shared/public/components/tour @elastic/platform-onboarding
 /x-pack/test/functional/apps/infra/tour.ts @elastic/platform-onboarding
 
 # Observability settings
@@ -1570,7 +1570,7 @@ x-pack/plugins/translations/translations
 x-pack/test/profiling_api_integration @elastic/obs-ux-infra_services-team
 
 # Observability shared profiling
-x-pack/plugins/observability_shared/public/components/profiling @elastic/obs-ux-infra_services-team
+x-pack/plugins/observability_solution/observability_shared/public/components/profiling @elastic/obs-ux-infra_services-team
 
 # Shared UX
 packages/react @elastic/appex-sharedux

api_docs/deprecations_by_plugin.mdx

@@ -1221,7 +1221,7 @@ tags: ['contributor', 'dev', 'apidocs', 'kibana']
 
 | Deprecated API | Reference location(s) | Remove By |
 | ---------------|-----------|-----------|
-| <DocLink id="kibKibanaReactPluginApi" section="def-public.toMountPoint" text="toMountPoint"/> | [header_menu_portal.tsx](https://github.com/elastic/kibana/tree/main/x-pack/plugins/observability_shared/public/components/header_menu/header_menu_portal.tsx#:~:text=toMountPoint), [header_menu_portal.tsx](https://github.com/elastic/kibana/tree/main/x-pack/plugins/observability_shared/public/components/header_menu/header_menu_portal.tsx#:~:text=toMountPoint) | - |
+| <DocLink id="kibKibanaReactPluginApi" section="def-public.toMountPoint" text="toMountPoint"/> | [header_menu_portal.tsx](https://github.com/elastic/kibana/tree/main/x-pack/plugins/observability_solution/observability_shared/public/components/header_menu/header_menu_portal.tsx#:~:text=toMountPoint), [header_menu_portal.tsx](https://github.com/elastic/kibana/tree/main/x-pack/plugins/observability_solution/observability_shared/public/components/header_menu/header_menu_portal.tsx#:~:text=toMountPoint) | - |
 
 
 

api_docs/kibana_react.devdocs.json

@@ -2722,11 +2722,11 @@
           },
           {
             "plugin": "observabilityShared",
-            "path": "x-pack/plugins/observability_shared/public/components/header_menu/header_menu_portal.tsx"
+            "path": "x-pack/plugins/observability_solution/observability_shared/public/components/header_menu/header_menu_portal.tsx"
           },
           {
             "plugin": "observabilityShared",
-            "path": "x-pack/plugins/observability_shared/public/components/header_menu/header_menu_portal.tsx"
+            "path": "x-pack/plugins/observability_solution/observability_shared/public/components/header_menu/header_menu_portal.tsx"
           },
           {
             "plugin": "telemetry",