Let notifications use avatar fallback.

Extract code which handles Matrix image to its own api / impl / test modules.

plugins/src/main/kotlin/extension/DependencyHandleScope.kt

@@ -90,6 +90,7 @@ fun DependencyHandlerScope.allLibrariesImpl() {
     implementation(project(":libraries:designsystem"))
     implementation(project(":libraries:matrix:impl"))
     implementation(project(":libraries:matrixui"))
+    implementation(project(":libraries:matrixmedia:impl"))
     implementation(project(":libraries:network"))
     implementation(project(":libraries:core"))
     implementation(project(":libraries:eventformatter:impl"))