Force last owner of a room to pass ownership when leaving (#5094)

* Move `ChangeRoles*` classes to their own module so they can be shared

* Hook the change roles screen to the leave room action, add confirmation dialogs

* Use enum instead of sealed interface for `ChangeRoomMemberRolesListType`

* Try to improve communications between nodes

* refactor (leave room) : makes sure to expose only necessary code from api module

* Add `:libraries:previewutils` module to share some test fixtures used for UI previews

* Update screenshots

---------

Co-authored-by: ElementBot <android@element.io>
Co-authored-by: ganfra <francoisg@matrix.org>

libraries/previewutils/build.gradle.kts

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2022-2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+plugins {
+    id("io.element.android-library")
+}
+
+android {
+    namespace = "io.element.android.libraries.previewutils"
+
+    dependencies {
+        implementation(projects.libraries.designsystem)
+        implementation(projects.libraries.matrix.api)
+
+        implementation(libs.kotlinx.collections.immutable)
+    }
+}