fix(watch): remove default list row backgrounds for cleaner UI

targets/watch/ContentView.swift

@@ -42,6 +42,7 @@ struct WorkoutListView: View {
                     }
                     .frame(maxWidth: .infinity)
                     .padding(.vertical, 20)
+                    .listRowBackground(.clear)
                 }
             } else {
                 Section("Saved Workouts") {
@@ -64,6 +65,7 @@ struct WorkoutListView: View {
                                     .font(.caption)
                             }
                         }
+                        .listRowBackground(.clear)
                     }
                     .onDelete { indexSet in
                         workoutManager.deleteSavedWorkouts(at: indexSet)
@@ -87,6 +89,7 @@ struct WorkoutListView: View {
                                     .foregroundColor(.green)
                                     .font(.caption)
                             }
+                            .listRowBackground(.clear)
                         }
                         .onDelete { indexSet in
                             workoutManager.deleteCompletedWorkouts(at: indexSet)

targets/watch/Views/WorkoutDetailView.swift

@@ -33,6 +33,7 @@ struct WorkoutDetailView: View {
                                 .font(.caption)
                                 .foregroundColor(.secondary)
                         }
+                        .listRowBackground(.clear)
                     }
                 }
 
@@ -57,6 +58,7 @@ struct WorkoutDetailView: View {
                     .font(.caption)
                     .foregroundColor(.secondary)
                     .frame(maxWidth: .infinity)
+                    .listRowBackground(.clear)
                 }
             }
         }

targets/watch/Views/WorkoutSummaryView.swift

@@ -18,6 +18,7 @@ struct WorkoutSummaryView: View {
                     }
                     .frame(maxWidth: .infinity)
                     .padding(.vertical, 8)
+                    .listRowBackground(.clear)
                 }
 
                 Section("Stats") {
@@ -28,6 +29,7 @@ struct WorkoutSummaryView: View {
                         Text(formatTime(summary.duration))
                             .monospacedDigit()
                     }
+                    .listRowBackground(.clear)
 
                     HStack {
                         Text("Distance")
@@ -36,6 +38,7 @@ struct WorkoutSummaryView: View {
                         Text("\(summary.totalDistance)m")
                             .monospacedDigit()
                     }
+                    .listRowBackground(.clear)
 
                     HStack {
                         Text("Calories")
@@ -44,6 +47,7 @@ struct WorkoutSummaryView: View {
                         Text("\(summary.calories)kcal")
                             .monospacedDigit()
                     }
+                    .listRowBackground(.clear)
 
                     HStack {
                         Text("Laps")
@@ -52,6 +56,7 @@ struct WorkoutSummaryView: View {
                         Text("\(summary.laps.count)")
                             .monospacedDigit()
                     }
+                    .listRowBackground(.clear)
                 }
 
                 Section {