Show multiplayer/playlist header content inside title wedge

Closes ppy#37077.

Author: peppy

osu.Game/Screens/OnlinePlay/Multiplayer/MultiplayerMatchSongSelect.cs

@@ -83,7 +83,7 @@ public MultiplayerMatchSongSelect(Room room, PlaylistItem? itemToEdit = null)
             initialItem = itemToEdit ?? room.Playlist.LastOrDefault();
 
             Padding = new MarginPadding { Horizontal = HORIZONTAL_OVERFLOW_PADDING };
-            LeftPadding = new MarginPadding { Top = CORNER_RADIUS_HIDE_OFFSET + Header.HEIGHT };
+            TopPadding = Header.HEIGHT - 10;
 
             freeModSelect = new FreeModSelectOverlay
             {

osu.Game/Screens/OnlinePlay/Playlists/PlaylistsSongSelect.cs

@@ -51,7 +51,7 @@ public PlaylistsSongSelect(Room room)
             ShowOsuLogo = false;
 
             Padding = new MarginPadding { Horizontal = HORIZONTAL_OVERFLOW_PADDING };
-            LeftPadding = new MarginPadding { Top = CORNER_RADIUS_HIDE_OFFSET + Header.HEIGHT };
+            TopPadding = Header.HEIGHT - 10;
 
             addToPlaylistFooterButton = new AddToPlaylistFooterButton
             {

osu.Game/Screens/Select/BeatmapTitleWedge.cs

@@ -46,6 +46,8 @@ public partial class BeatmapTitleWedge : VisibilityContainer
         [Resolved]
         private IBindable<SongSelect.BeatmapSetLookupResult?> onlineLookupResult { get; set; } = null!;
 
+        public float TopPadding { get; init; }
+
         protected override bool StartHidden => true;
 
         private ModSettingChangeTracker? settingChangeTracker;
@@ -97,7 +99,7 @@ private void load()
                     Direction = FillDirection.Vertical,
                     Padding = new MarginPadding
                     {
-                        Top = SongSelect.WEDGE_CONTENT_MARGIN,
+                        Top = SongSelect.WEDGE_CONTENT_MARGIN + TopPadding,
                         Left = SongSelect.WEDGE_CONTENT_MARGIN
                     },
                     Spacing = new Vector2(0f, 4f),

osu.Game/Screens/Select/SongSelect.cs

@@ -99,7 +99,11 @@ public abstract partial class SongSelect : ScreenWithBeatmapBackground, IKeyBind
         /// </summary>
         protected bool ShowOsuLogo { get; init; } = true;
 
-        protected MarginPadding LeftPadding { get; init; }
+        /// <summary>
+        /// Additional padding to be added to the title wedge.
+        /// Generally set to show external content in this space.
+        /// </summary>
+        public float TopPadding { get; init; }
 
         private ModSelectOverlay modSelectOverlay = null!;
         private ModSpeedHotkeyHandler modSpeedHotkeyHandler = null!;
@@ -233,10 +237,12 @@ private void load(AudioManager audio, OsuConfigManager config)
                                                         RelativeSizeAxes = Axes.Both,
                                                         Spacing = new Vector2(0f, 4f),
                                                         Direction = FillDirection.Vertical,
-                                                        Padding = LeftPadding,
                                                         Children = new Drawable[]
                                                         {
-                                                            new ShearAligningWrapper(titleWedge = new BeatmapTitleWedge()),
+                                                            new ShearAligningWrapper(titleWedge = new BeatmapTitleWedge
+                                                            {
+                                                                TopPadding = TopPadding,
+                                                            }),
                                                             new ShearAligningWrapper(detailsArea = new BeatmapDetailsArea()),
                                                         },
                                                     },