fix(ui): refine track action spacing

lib/screens/artist_screen_widgets.dart

@@ -433,7 +433,7 @@ extension _ArtistScreenSections on _ArtistScreenState {
             hasLocalPlaybackCandidate: isInHistory || isInLocalLibrary,
           ),
           child: Padding(
-            padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
+            padding: const EdgeInsets.fromLTRB(16, 8, 10, 8),
             child: Row(
               children: [
                 SizedBox(

lib/screens/home_tab_widgets.dart

@@ -269,7 +269,7 @@ class _TrackItemWithStatus extends ConsumerWidget {
           splashColor: colorScheme.primary.withValues(alpha: 0.12),
           highlightColor: colorScheme.primary.withValues(alpha: 0.08),
           child: Padding(
-            padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
+            padding: const EdgeInsets.fromLTRB(12, 10, 6, 10),
             child: Row(
               children: [
                 ClipRRect(

lib/widgets/track_card.dart

@@ -77,6 +77,9 @@ class TrackCard extends StatelessWidget {
     final theme = Theme.of(context);
     final colorScheme = theme.colorScheme;
     final borderRadius = tokens.borderRadiusCover;
+    final contentPadding = style == TrackCardStyle.flat
+        ? EdgeInsets.fromLTRB(tokens.gapMd, tokens.gapMd, 6, tokens.gapMd)
+        : EdgeInsets.all(tokens.gapMd);
 
     final Color? cardColor;
     if (isSelected) {
@@ -111,7 +114,7 @@ class TrackCard extends StatelessWidget {
           children: [
             if (background != null) Positioned.fill(child: background!),
             Padding(
-              padding: EdgeInsets.all(tokens.gapMd),
+              padding: contentPadding,
               child: Row(
                 children: [
                   if (isSelectionMode) ...[

lib/widgets/track_collection_quick_actions.dart

@@ -59,7 +59,7 @@ class TrackCollectionQuickActions extends ConsumerWidget {
         track,
         hasLocalPlaybackCandidate: hasLocalPlaybackCandidate,
       ),
-      padding: const EdgeInsets.only(left: 12),
+      padding: EdgeInsets.zero,
       constraints: const BoxConstraints(minWidth: 48, minHeight: 48),
     );
   }