Implement month separator for the Gallery.

Improve day separator rendering in the timeline.
Use Today, Yesterday, and the name of the day if less than 7 days and do not render the year for the current year.
Improve date format for the media viewer.
Rework how date and time are computed.
ActionListView: Time can take more space, so update the layout.

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

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.libraries.dateformatter.test
+
+import io.element.android.libraries.dateformatter.api.DateFormatter
+import io.element.android.libraries.dateformatter.api.DateFormatterMode
+
+class FakeDateFormatter(
+    private val formatLambda: (Long?, DateFormatterMode, Boolean) -> String = { timestamp, mode, useRelative ->
+        "$timestamp $mode $useRelative"
+    },
+) : DateFormatter {
+    override fun format(
+        timestamp: Long?,
+        mode: DateFormatterMode,
+        useRelative: Boolean,
+    ): String {
+        return formatLambda(timestamp, mode, useRelative)
+    }
+}

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

@@ -1,22 +0,0 @@
-/*
- * Copyright 2023, 2024 New Vector Ltd.
- *
- * SPDX-License-Identifier: AGPL-3.0-only
- * Please see LICENSE in the repository root for full details.
- */
-
-package io.element.android.libraries.dateformatter.test
-
-import io.element.android.libraries.dateformatter.api.DaySeparatorFormatter
-
-class FakeDaySeparatorFormatter : DaySeparatorFormatter {
-    private var format = ""
-
-    fun givenFormat(format: String) {
-        this.format = format
-    }
-
-    override fun format(timestamp: Long): String {
-        return format
-    }
-}

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

@@ -1,24 +0,0 @@
-/*
- * Copyright 2023, 2024 New Vector Ltd.
- *
- * SPDX-License-Identifier: AGPL-3.0-only
- * Please see LICENSE in the repository root for full details.
- */
-
-package io.element.android.libraries.dateformatter.test
-
-import io.element.android.libraries.dateformatter.api.LastMessageTimestampFormatter
-
-const val A_FORMATTED_DATE = "formatted_date"
-
-class FakeLastMessageTimestampFormatter(
-    var format: String = "",
-) : LastMessageTimestampFormatter {
-    fun givenFormat(format: String) {
-        this.format = format
-    }
-
-    override fun format(timestamp: Long?): String {
-        return format
-    }
-}