Add a new RoomThreadListScreen and hook it up to the RoomThreadListService

It will automatically paginate to fill the screen and update the list as updates come in.

PreviewTests/Sources/GeneratedPreviewTests.swift

@@ -1179,6 +1179,14 @@ extension PreviewTests {
         }
     }
 
+    @Test
+    func roomThreadListScreen() async throws {
+        AppSettings.resetAllSettings() // Ensure this test's previews start with fresh settings.
+        for (index, preview) in RoomThreadListScreen_Previews._allPreviews.enumerated() {
+            try await assertSnapshots(matching: preview, step: index)
+        }
+    }
+
     @Test
     func sFNumberedListView() async throws {
         AppSettings.resetAllSettings() // Ensure this test's previews start with fresh settings.