Add an empty state for the space screen if the user can modify its graph (#6064)

* Add an empty state for the space screen if the user can modify its graph. It adds a new 'create room' button that allows you to open the create room screen with some preset values.

* When computing the editable spaces in `ConfigureRoomPresenter`, also set up the initial selected parent space if possible

* Use `Builder` pattern for `CreateRoomEntryPoint`

* Update screenshots

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Co-authored-by: ElementBot <android@element.io>

appnav/src/main/kotlin/io/element/android/appnav/LoggedInFlowNode.kt

@@ -484,7 +484,10 @@ class LoggedInFlowNode(
                         backstack.replace(NavTarget.Room(roomIdOrAlias = RoomIdOrAlias.Id(roomId), serverNames = emptyList()))
                     }
                 }
-                createRoomEntryPoint.createNode(isSpace = true, parentNode = this, buildContext = buildContext, callback = callback)
+                createRoomEntryPoint
+                    .builder(parentNode = this, buildContext = buildContext, callback = callback)
+                    .setIsSpace(true)
+                    .build()
             }
             is NavTarget.SecureBackup -> {
                 secureBackupEntryPoint.createNode(