refactor: prepare to decouple the "model migration" package and "models" package (#38533)

Migrations should never use model structs directly, because the model
structs can be different in different releases. e.g. if one migration uses
"User" model, it works in the early releases, then one day, when the
User model changes, the migration breaks because it will use the
new (incorrect) User model, it should only use the old User model.

The same to "modules/structs".

---------

Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: delvh <dev.lh@web.de>

modelmigration/v1_10/v99.go

@@ -0,0 +1,37 @@
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v1_10
+
+import (
+	"gitea.dev/modelmigration/base"
+	"gitea.dev/modules/timeutil"
+)
+
+func AddTaskTable(x base.EngineMigration) error {
+	// TaskType defines task type
+	type TaskType int
+
+	// TaskStatus defines task status
+	type TaskStatus int
+
+	type Task struct {
+		ID             int64
+		DoerID         int64 `xorm:"index"` // operator
+		OwnerID        int64 `xorm:"index"` // repo owner id, when creating, the repoID maybe zero
+		RepoID         int64 `xorm:"index"`
+		Type           TaskType
+		Status         TaskStatus `xorm:"index"`
+		StartTime      timeutil.TimeStamp
+		EndTime        timeutil.TimeStamp
+		PayloadContent string             `xorm:"TEXT"`
+		Errors         string             `xorm:"TEXT"` // if task failed, saved the error reason
+		Created        timeutil.TimeStamp `xorm:"created"`
+	}
+
+	type Repository struct {
+		Status int `xorm:"NOT NULL DEFAULT 0"`
+	}
+
+	return x.Sync(new(Task), new(Repository))
+}