DashboardScene: Viewer role only support (#76748)

* Allow starring DashboardScene

* Add feature toggle to enable dashbaord scene for viewers

* Basics for proxying viewers to a dashboard scene

* Removed isHomeDashboard flag

* Don't use proxy for rendering dashboard page

* Revert "Don't use proxy for rendering dashboard page"

This reverts commit 95836bdb2c.

* Pre-fetch dashboard prior page rendering

* Depend only on dashboard permissions

* Update default home dashboard to proper model...

* Fix breadcrumbs

* Types update

* Dashboards page proxy tests

* Fix missing controls

* URLs generation

* DashboardScenePageStateManager caching test

* Tests updates

* Fix wrong import

* Test update

* Gen

public/dashboards/home.json

@@ -23,16 +23,18 @@
         "x": 0,
         "y": 4
       },
-      "headings": true,
       "id": 3,
-      "limit": 30,
       "links": [],
-      "options": {},
-      "query": "",
-      "recent": true,
-      "search": false,
-      "starred": true,
-      "tags": [],
+      "options": {
+        "showStarred": true,
+        "showRecentlyViewed": true,
+        "showSearch": false,
+        "showHeadings": true,
+        "folderId": 0,
+        "maxItems": 30,
+        "tags":[],
+        "query": ""
+      }, 
       "title": "Dashboards",
       "type": "dashlist"
     },