Sustainable Kibana Architecture: Move modules owned by @elastic/observability-ui (#202834)

## Summary

This PR aims at relocating some of the Kibana modules (plugins and
packages) into a new folder structure, according to the _Sustainable
Kibana Architecture_ initiative.

> [!IMPORTANT]
> * We kindly ask you to:
> * Manually fix the errors in the error section below (if there are
any).
> * Search for the `packages[\/\\]` and `plugins[\/\\]` patterns in the
source code (Babel and Eslint config files), and update them
appropriately.
> * Manually review
`.buildkite/scripts/pipelines/pull_request/pipeline.ts` to ensure that
any CI pipeline customizations continue to be correctly applied after
the changed path names
> * Review all of the updated files, specially the `.ts` and `.js` files
listed in the sections below, as some of them contain relative paths
that have been updated.
> * Think of potential impact of the move, including tooling and
configuration files that can be pointing to the relocated modules. E.g.:
>     * customised eslint rules
>     * docs pointing to source code

> [!NOTE]
> * This PR has been auto-generated.
> * Any manual contributions will be lost if the 'relocate' script is
re-run.
> * Try to obtain the missing reviews / approvals before applying manual
fixes, and/or keep your changes in a .patch / git stash.
> * Please use
[#sustainable_kibana_architecture](https://elastic.slack.com/archives/C07TCKTA22E)
Slack channel for feedback.

Are you trying to rebase this PR to solve merge conflicts? Please follow
the steps describe
[here](https://elastic.slack.com/archives/C07TCKTA22E/p1734019532879269?thread_ts=1734019339.935419&cid=C07TCKTA22E).

#### 1 plugin(s) are going to be relocated:

| Id | Target folder |
| -- | ------------- |
| `@kbn/observability-shared-plugin` |
`x-pack/solutions/observability/plugins/observability_shared` |




#### 3 packages(s) are going to be relocated:

| Id | Target folder |
| -- | ------------- |
| `@kbn/observability-utils-browser` |
`x-pack/solutions/observability/packages/utils_browser` |
| `@kbn/observability-utils-common` |
`x-pack/solutions/observability/packages/utils_common` |
| `@kbn/observability-utils-server` |
`x-pack/solutions/observability/packages/utils_server` |


<details >
<summary>Updated references</summary>

```
./docs/developer/plugin-list.asciidoc
./package.json
./packages/kbn-repo-packages/package-map.json
./packages/kbn-ts-projects/config-paths.json
./src/dev/storybook/aliases.ts
./tsconfig.base.json
./tsconfig.base.type_check.json
./tsconfig.refs.json
./x-pack/.i18nrc.json
./x-pack/solutions/observability/packages/utils_browser/jest.config.js
./x-pack/solutions/observability/packages/utils_common/jest.config.js
./x-pack/solutions/observability/packages/utils_server/jest.config.js
./x-pack/solutions/observability/plugins/observability_shared/jest.config.js
./x-pack/test/tsconfig.type_check.json
./yarn.lock
.github/CODEOWNERS
```

</details><details >
<summary>Updated relative paths</summary>

```
x-pack/solutions/observability/packages/utils_browser/jest.config.js:10
x-pack/solutions/observability/packages/utils_browser/tsconfig.json:2
x-pack/solutions/observability/packages/utils_common/jest.config.js:10
x-pack/solutions/observability/packages/utils_common/tsconfig.json:2
x-pack/solutions/observability/packages/utils_server/jest.config.js:10
x-pack/solutions/observability/packages/utils_server/tsconfig.json:2
x-pack/solutions/observability/plugins/observability_shared/jest.config.js:10
x-pack/solutions/observability/plugins/observability_shared/tsconfig.json:12
x-pack/solutions/observability/plugins/observability_shared/tsconfig.json:2
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:102
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:105
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:108
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:111
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:114
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:14
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:2
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:21
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:24
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:27
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:30
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:33
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:36
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:39
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:42
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:45
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:48
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:51
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:54
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:57
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:60
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:63
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:66
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:69
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:72
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:75
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:78
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:81
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:84
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:87
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:90
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:93
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:96
x-pack/solutions/observability/plugins/observability_shared/tsconfig.type_check.json:99
```

</details>

---------

Co-authored-by: kibanamachine <42973632+kibanamachine@users.noreply.github.com>
Co-authored-by: pgayvallet <pierre.gayvallet@elastic.co>

docs/developer/plugin-list.asciidoc

@@ -764,7 +764,7 @@ Elastic.
 |This plugin provides an onboarding framework for observability solutions: Logs and APM.
 
 
-|{kib-repo}blob/{branch}/x-pack/plugins/observability_solution/observability_shared/README.md[observabilityShared]
+|{kib-repo}blob/{branch}/x-pack/solutions/observability/plugins/observability_shared/README.md[observabilityShared]
 |A plugin that contains components and utilities shared by all Observability plugins.