[Solution Side Nav] Remove PanelContentProvider & support optional title in nav node

[tsullivan]

Epic: https://github.com/elastic/kibana-team/issues/1439
Needed for #218050 (adjustments to types for title field in ChromeProjectNavigationNode)

Summary

1. PanelContentProvider was used for security solution, but is no longer used. This removes it to simplify the interfaces for panel .
2. Allow title of navGroup to be optional. This allows the correct design for nav items in the footer, which are child-items of a nav group with no title

Progress towards fixing footer issues

The look and feel of nav items in the footer was wrong. Now that navGroup titles are optional, we can make footer navigation items appear more like the intended design. Run the yarn storybook shared_ux and view the Chrome Navigation page for the proper way footer nav items should look.

Storybook before	Storybook after

To achieve this fix within Solutions, teams will need to update their navigation structure and move the top-level footer items into a single navGroup.

Example code fix

File: x-pack/solutions/observability/plugins/observability/public/navigation_tree.ts

Explanation:
* Structure the footer with a single `navGroup` containing the nav footer contents as sub-items
   * i.e., replace the structure of: `navItem / navItem / navGroup`
* Do not add a `title` for this `navGroup`
* For Stack Management, use `renderAs: 'accordion'` and `spaceBefore: null`
* Remove `recentlyAccessed` for now

@@ -325,9 +325,10 @@ function createNavTree({ streamsAvailable }: { streamsAvailable?: boolean }) {
       },
     ],
     footer: [
-      { type: 'recentlyAccessed' },
       {
-        type: 'navItem',
+        type: 'navGroup',
+        id: 'observability_project_nav_footer',
+        children: [
+          {
             title: i18n.translate('xpack.observability.obltNav.addData', {
               defaultMessage: 'Add data',
             }),
@@ -335,7 +336,6 @@ function createNavTree({ streamsAvailable }: { streamsAvailable?: boolean }) {
             icon: 'launch',
           },
           {
-        type: 'navItem',
             id: 'devTools',
             title: i18n.translate('xpack.observability.obltNav.devTools', {
               defaultMessage: 'Developer tools',
@@ -344,13 +344,14 @@ function createNavTree({ streamsAvailable }: { streamsAvailable?: boolean }) {
             icon: 'editorCodeBlock',
           },
           {
-        type: 'navGroup',
             id: 'project_settings_project_nav',
             title: i18n.translate('xpack.observability.obltNav.management', {
               defaultMessage: 'Management',
             }),
             icon: 'gear',
             breadcrumbStatus: 'hidden',
+            renderAs: 'accordion',
+            spaceBefore: null,
             children: [
               {
                 id: 'stack_management',
@@ -455,6 +456,8 @@ function createNavTree({ streamsAvailable }: { streamsAvailable?: boolean }) {
             ],
           },
         ],
+      },
+    ],
   };

Checklist

Check the PR satisfies following conditions.

Reviewers should verify this PR satisfies this list as well.

• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios

[elasticmachine]

Pinging @elastic/appex-sharedux (Team:SharedUX)

[tsullivan]

I'm not entirely sure why this was necessary 🤔

[tsullivan]

footer should have a single group of sub-items, with no title for that group

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 6701575
• Storybooks Preview

Metrics [docs]

Public APIs missing comments

Total count of every public API that lacks a comment. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats comments for more detailed information.

id	before	after	diff
@kbn/shared-ux-chrome-navigation	29	26	-3
serverless	24	23	-1
total			-4

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
navigation	18.9KB	18.6KB	-296.0B
serverless	19.6KB	19.3KB	-296.0B
total			-592.0B

Public APIs missing exports

Total count of every type that is part of your API that should be exported but is not. This will cause broken links in the API documentation system. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats exports for more detailed information.

id	before	after	diff
@kbn/core	872	873	+1

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
core	433.2KB	433.2KB	+6.0B
navigation	12.8KB	12.7KB	-92.0B
serverless	9.7KB	9.6KB	-46.0B
total			-132.0B

Unknown metric groups

API count

id	before	after	diff
@kbn/shared-ux-chrome-navigation	38	35	-3
serverless	24	23	-1
total			-4

History

• 💚 Build #292977 succeeded f471af8
• 💔 Build #292932 failed 9a88105
• 💔 Build #292904 failed 9a88105

[kibanamachine]

Starting backport for target branches: 8.x

https://github.com/elastic/kibana/actions/runs/14472802881

[kibanamachine]

💔 All backports failed

Status	Branch	Result
❌	8.x	Backport failed because of merge conflicts

Manual backport

To create the backport manually run:

node scripts/backport --pr 218156

Questions ?

Please refer to the Backport tool documentation

[tsullivan]

💚 All backports created successfully

Status	Branch	Result
✅	8.x

Note: Successful backport PRs will be merged automatically after passing CI.

Questions ?

Please refer to the Backport tool documentation