feat: убираем денормализацию (антипреждевременная оптимизация)

src/usecase/creative/update_creative.py

@@ -35,6 +35,8 @@ async def update_creative(
 
     await self.database.update_creative(creative)
 
+    placements_count = await self.database.count_placements_by_creative(creative.id)
+
     return dto.CreativeOutput(
         id=creative.id,
         name=creative.name,
@@ -43,5 +45,5 @@ async def update_creative(
         project_channel_title=creative.project.channel.title,
         created_at=creative.created_at,
         status=creative.status,
-        placements_count=creative.placements_count,
+        placements_count=placements_count,
     )