ML-142: Improve scrobble UI in the release component

- Sticky bar for easier track-based scrobbling
- Support setting custom finish time

test/music_library_web/live/collection_live/show_test.exs

@@ -83,7 +83,7 @@ defmodule MusicLibraryWeb.CollectionLive.ShowTest do
         |> visit(~p"/collection/#{record.id}")
         |> assert_has("button", "Show Tracks")
         |> unwrap(&render_async/1)
-        |> assert_has("a", "Connect your Last.fm account")
+        |> assert_has("a", "Connect Last.fm")
 
       release =
         MusicBrainz.Release.from_api_response(release_response)

test/music_library_web/live/scrobble_live/show_test.exs

@@ -112,6 +112,23 @@ defmodule MusicLibraryWeb.ScrobbleLive.ShowTest do
       |> assert_has("#toast-group", "Disc scrobbled successfully")
     end
 
+    test "scrobble single medium still works with tracks selected elsewhere", %{conn: conn} do
+      track_id = first_track_id()
+      session = visit(conn, ~p"/scrobble/#{@release_id}")
+
+      session
+      |> unwrap(fn view ->
+        # Select a track first — AC#3 regression: medium scrobble must not be
+        # blocked just because something is ticked.
+        view
+        |> element("#scrobble-release-form")
+        |> render_change(%{"release" => %{"selected_tracks" => [track_id]}})
+
+        render_click(view, "scrobble_medium", %{"number" => "1"})
+      end)
+      |> assert_has("#toast-group", "Disc scrobbled successfully")
+    end
+
     test "toggle track on and off changes button label", %{conn: conn} do
       track_id = first_track_id()