Explore: Make toolbar action extendable by plugins (#65524)

* Cleaned up solution and starting to make it work properly.

* will disable add button if no queries available.

* Changed so 'add to dashboard' is registered as an extension in explore.

* moved utility function to utils

* hides button if insufficent permissions.

* Fixed ts issue.

* cleaned up the code and change to using the 'getPluginLinkExtensions'

* Added values to explore context.

* truncating title in menu.

* added tests to verify explore extension point.

* fixed failing tests in explore.

* made excludeModal optional.

* removed temporary fix to force old button.

* reverted generated files.

* fixed according to feedback.

* Update public/app/features/explore/extensions/ToolbarExtensionPoint.test.tsx

Co-authored-by: Levente Balogh <balogh.levente.hu@gmail.com>

* Update public/app/features/explore/extensions/ToolbarExtensionPoint.test.tsx

Co-authored-by: Levente Balogh <balogh.levente.hu@gmail.com>

* added tests suggested in reviews.

* fixed failing tests after sync with main.

* replaced exploreId type with stirng.

* cleaned up code a bit more.

---------

Co-authored-by: Levente Balogh <balogh.levente.hu@gmail.com>

packages/grafana-data/src/types/pluginExtensions.ts

@@ -4,6 +4,7 @@ import { DataQuery, DataSourceJsonData } from '@grafana/schema';
 
 import { ScopedVars } from './ScopedVars';
 import { DataSourcePluginMeta, DataSourceSettings } from './datasource';
+import { IconName } from './icon';
 import { PanelData } from './panel';
 import { RawTimeRange, TimeZone } from './time';
 
@@ -27,6 +28,7 @@ export type PluginExtensionLink = PluginExtensionBase & {
   type: PluginExtensionTypes.link;
   path?: string;
   onClick?: (event?: React.MouseEvent) => void;
+  icon?: IconName;
 };
 
 export type PluginExtensionComponent = PluginExtensionBase & {
@@ -62,8 +64,12 @@ export type PluginExtensionLinkConfig<Context extends object = object> = {
         description: string;
         path: string;
         onClick: (event: React.MouseEvent | undefined, helpers: PluginExtensionEventHelpers<Context>) => void;
+        icon: IconName;
       }>
     | undefined;
+
+  // (Optional) A icon that can be displayed in the ui for the extension option.
+  icon?: IconName;
 };
 
 export type PluginExtensionComponentConfig<Context extends object = object> = {
@@ -100,6 +106,7 @@ export type PluginExtensionEventHelpers<Context extends object = object> = {
 export enum PluginExtensionPoints {
   DashboardPanelMenu = 'grafana/dashboard/panel/menu',
   DataSourceConfig = 'grafana/datasources/config',
+  ExploreToolbarAction = 'grafana/explore/toolbar/action',
 }
 
 export type PluginExtensionPanelContext = {