feat(stats): flip home Plays card live (Phase 16.5)

Add TotalPlays + UniqueListeners to HomeStatsDto, composed at
StatsController from IEventService (no migration). Card reads via
existing persistent-state-bridged round-trip.

DeepDrftData/EventManager.cs

@@ -54,6 +54,20 @@ public class EventManager : IEventService
         }
     }
 
+    public async Task<ResultContainer<long>> GetTotalPlayCount(CancellationToken cancellationToken = default)
+    {
+        try
+        {
+            var count = await _repository.CountTotalPlaysAsync(cancellationToken);
+            return ResultContainer<long>.CreatePassResult(count);
+        }
+        catch (Exception e)
+        {
+            _logger.LogError(e, "Failed to count total plays");
+            return ResultContainer<long>.CreateFailResult(e.Message);
+        }
+    }
+
     public async Task<ResultContainer<int>> GetDistinctListenerCount(CancellationToken cancellationToken = default)
     {
         try