Sync notifications using WorkManager (#5545)

* Initial implementation of notification sync using `WorkManager`

* Use custom `MetroWorkerFactory` to allow assisted injection in WorkManager Workers

* Add tests for `FetchNotificationWorker`. Create `FakeNotificationResolverQueue` to help testing.

* Add more tests, fix Konsist checks

* Add tests for `SyncNotificationWorkManagerRequest`

* Simplify `FakeNotificationResolverQueue`

libraries/workmanager/test/build.gradle.kts

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2025 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.workmanager.test"
+}
+
+dependencies {
+    api(projects.libraries.workmanager.api)
+    implementation(projects.libraries.matrix.api)
+    implementation(projects.tests.testutils)
+}