[fenix] closes https://github.com/mozilla-mobile/fenix/issues/24306: add nav argument to open tabs tray to an initial page

app/src/main/java/org/mozilla/fenix/tabstray/TabsTrayFragment.kt

@@ -131,10 +131,12 @@ class TabsTrayFragment : AppCompatDialogFragment() {
         } else {
             TabsTrayState.Mode.Normal
         }
+        val initialPage = args.page
 
         tabsTrayStore = StoreProvider.get(this) {
             TabsTrayStore(
                 initialState = TabsTrayState(
+                    selectedPage = initialPage,
                     mode = initialMode,
                     focusGroupTabId = args.focusGroupTabId
                 ),

app/src/main/res/navigation/nav_graph.xml

@@ -162,6 +162,11 @@
             app:nullable="true"
             android:defaultValue="@null"
             app:argType="string" />
+        <argument
+            android:name="page"
+            android:defaultValue="NormalTabs"
+            app:argType="org.mozilla.fenix.tabstray.Page"
+            />
     </dialog>
 
     <fragment