refactor(repository): 收敛 model/repository 分层为唯一持久化入口

将 OpenFlare 与平台业务的数据访问从 model 与 apps 直连迁入 repository，
model 仅保留实体与无 IO 规则；补充 code-check 架构守卫与开发规范。

internal/apps/upload/task/tasks_test.go

@@ -17,6 +17,8 @@ import (
 	"testing"
 	"time"
 
+	"github.com/Rain-kl/Wavelet/internal/repository"
+
 	"github.com/Rain-kl/Wavelet/internal/apps/upload/filesrv"
 	"github.com/Rain-kl/Wavelet/internal/apps/upload/shared"
 	uploadstats "github.com/Rain-kl/Wavelet/internal/apps/upload/stats"
@@ -129,7 +131,7 @@ func TestSystemCleanupHandler_Execute(t *testing.T) {
 		UpdatedAt:   now.AddDate(0, 0, -31),
 		TriggeredBy: "system",
 	}
-	err = model.CreateTaskExecution(ctx, oldTaskLog)
+	err = repository.CreateTaskExecution(ctx, oldTaskLog)
 	require.NoError(t, err)
 
 	// 执行 handler