Use formatter for LLS duration

libraries/dateformatter/test/src/main/kotlin/io/element/android/libraries/dateformatter/test/FakeDurationFormatter.kt

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.test
+
+import io.element.android.libraries.dateformatter.api.DurationFormatter
+import kotlin.time.Duration
+
+class FakeDurationFormatter(
+    private val formatLambda: (Duration) -> String = { it.toString() },
+) : DurationFormatter {
+    override fun format(duration: Duration): String {
+        return formatLambda(duration)
+    }
+}